3 Ways Jhoan Duran Can Reach Another Level in 2023

Thank you Cody, for this article about Duran. I have 2 questions.

I always thought his split finger FB (splinker) was his best pitch, why the discrepancy?

If Duran pitched better in the 2nd half by pitching fewer multiple innings games why is that a reason for him to pitch more multiple innings games?

I'm genuinely interested because I'd like to see Duran to be even better.

"The Twins used him as a starter throughout his professional career", to me is the key point in any Duran discussion.  What if the lock down ace # 1 we so desire is right under our noses?  It's not like he had disappointing results as a starter in the minors.  Hell, those numbers were good enough for us to want to get him into the big leagues in any role.  I always felt like we left a little something on the table a while back when we never found a way to get Trevor May back into the rotation and I think we'd be doing the same here.  Speaking of May, he currently projects to be the highest paid pitcher for the A's this season at about $6 Million.  When the selloff begins and we're once again looking for bullpen help, that's a call we should be making.

24 minutes ago, dxpavelka said:

"The Twins used him as a starter throughout his professional career", to me is the key point in any Duran discussion.  What if the lock down ace # 1 we so desire is right under our noses?  It's not like he had disappointing results as a starter in the minors.  Hell, those numbers were good enough for us to want to get him into the big leagues in any role.  I always felt like we left a little something on the table a while back when we never found a way to get Trevor May back into the rotation and I think we'd be doing the same here.  Speaking of May, he currently projects to be the highest paid pitcher for the A's this season at about $6 Million.  When the selloff begins and we're once again looking for bullpen help, that's a call we should be making.

He had injury concerns as a starter and I think he’ll have Jorge Lopez syndrome: a lights-out reliever or a 5.00 ERA starter, and I think everyone will pick the former.

Use Duran in high-leverage if you REALLY need him, but I’d say keep him as the prototypical Closer. When you have a 0.42 ERA in the 9th inning for more than 15 innings the closer role is yours undoubtedly.

Be able to go on back-to-back days a bit more regularly and effectively. He’s only did it five times last year. It’s SSS, but he gave up a run three of those times.

One of the best relievers in the game.  If it ain't broke, don't fix it!

1 hour ago, MTV said:

He had injury concerns as a starter and I think he’ll have Jorge Lopez syndrome: a lights-out reliever or a 5.00 ERA starter, and I think everyone will pick the former.

Duran's stuff is miles ahead of Lopez. If the Twins try Duran as a starter and it doesn't work out they can always move him right back to the bullpen. If it does work out they could have an ace at a minimum salary. It is hard for me to believe that they don't even want to try, especially since Duran wants to be a starter. It could be the team's biggest waste of talent since they released Luis Tiant.

I would prefer the Twins to have a more traditional pen where relievers know their roles. I've seen interviews with other relievers that have said they prefer it that way.

2 hours ago, Doctor Gast said:

Thank you Cody, for this article about Duran. I have 2 questions.

I always thought his split finger FB (splinker) was his best pitch, why the discrepancy?

If Duran pitched better in the 2nd half by pitching fewer multiple innings games why is that a reason for him to pitch more multiple innings games?

I'm genuinely interested because I'd like to see Duran to be even better.

I think as it pertains to the Splinker, is much like a hanging offspeed, when he missed with it, he could get hit hard.  Also, half of his HR is 3, and although he only threw the pitch at 16% he still threw it 163 times.  Being it averaged 96 MPH, compared to 4 seam at 100, or curve at 87.  He still got a whiff rate of 34% on it compared to only 26 on 4 seam.  My guess it generally would come down to location, where it would stay much more thigh high.  It would allow hitters to catch up to it, and was more in the zone compared to others. 

Working on getting off the zone more, or lower in zone will help I would say.  It is not like it is a bad pitch, but maybe not as good as we have been told.  His curve was much more effective.  

In terms of the more multi innings, I agree the logic seems to defy the numbers, that he did better with less multi inning games.  However, where maybe the writer should have included, was that if you look at his game logs.  From what I can see only 1 time did pitching in 2 innings actually have a negative result for him.  He allowed runs in 10 games all season.  Only 1 game was in the second inning of pitching, and the other 9 were in 1 inning outings.  I do recall a few times he may have pitched into a second inning and was pulled after allowing runners, that did not score, but overall he was fine with multi inning outings.  The only game was also April 15th.  

6 minutes ago, Karbo said:

I would prefer the Twins to have a more traditional pen where relievers know their roles. I've seen interviews with other relievers that have said they prefer it that way.

I think it can be both-and. In addition to having a traditional closer, traditional 8th-inning guy, traditional 7th-inning guy, I think it’s possible to have a “flexible high-leverage guy.”

In fact, I think a bullpen needs one of those. When Hader was coming on to the scene in Milwaukee, for example, that was his role. Corey Knebel was the primary closer, even though Hader was more effective. I didn’t pay close enough attention to how they used him — I was just frustrated that my fantasy team wasn’t getting every save.

In that way, I think it’s possible to have your second-best reliever be the “closer,” especially if he’s got experience there. So, for example, give Lopez the two- and three-run saves and the one-run saves against the bottom of the order, and assume he’ll lead the team in that category. Use Jax in the traditional eighth-inning role. But use Duran flexibly, in high-leverage spots — putting out fires in the seventh or eighth, one-run saves against the top of the order, the ninth when Lopez has already gone two-straight days, the four-or five-out save when Lopez has pitched the previous day and Duran finishes the eighth on six pitches, etc.

2 hours ago, Doctor Gast said:

Thank you Cody, for this article about Duran. I have 2 questions.

I always thought his split finger FB (splinker) was his best pitch, why the discrepancy?

If Duran pitched better in the 2nd half by pitching fewer multiple innings games why is that a reason for him to pitch more multiple innings games?

I'm genuinely interested because I'd like to see Duran to be even better.

It's true that Duran's splitter was his least effective pitch last year with a .353 wOBA against.  That's not terrible but he dominated more with his FB and curve/slider.

My guess is that the splinker was tougher against minor leaguers because it was so unique, but maybe isn't quite so unique to major league hitters.  My understanding is that it was the result of the Twins attempting help him develop a splitter to use against lefties as a starter.  It never quite developed the shape of a splitter and he throws it so hard, hence it became a unique hybrid "splinker".  While it is still pretty unique, there are plenty of major league pitchers with mid-90s sinkers (Jorge Lopez for example), so maybe it is not unique enough for major leaguers.

Since the difference in velocity from his fastball isn't huge, it doesn't quite function like a changeup, and MLB hitters seemed to have found it easier to hit than his fastball, probably in particular when he left it up in the zone.  I remember in particular probably his single worst outing when the Orioles hit two HR off of the splinker, both I think middle-in. location wise.

Hopefully he can improve on it this year, I think first and foremost with location, keeping it down where it's harder to do a lot of damage.  I also think it might work better for him if he finds a way to actually throw it a bit slower, making it harder for hitters to adjust their timing between his FB and splitter, and also giving the pitch a bit more drop.

As far as pitching more innings, even if he is less effective pitching more volume, as long as he is still more effective than the guys that would take those innings, that is still adding value.  There are of course other considerations, i.e. keeping him healthy as well.

There are also calls for him to go back to starting which would give him tons more volume, but starting is a whole different animal, and his lack of a true changeup makes me skeptical that it would work out as well as we might think.

Something of a side note that has been on my mind: I think the value of a truly dominant reliever isn't always fully appreciated anyway.  WAR calculations try to adjust for leverage, but I'm not convinced that they do enough.  BR, for example, has the leverage adjustment WAAadj.  According to them Duran's WAAadj was 0.4, his WAA (wins above average) was 1.8, and his WAR was 2.8.  However, his WPA was 4.6.  To get a different measure of his value to the Twins last year, my quick adjustment is to subtract WAA and WAAadj from WAR, and then add WPA, so 2.8 - 1.8 - 0.4 + 4.6 = 5.2 wins above replacement. Way above any of their starters and up there with Carlos Correa.

WPA is very noisy and not very predictive from year to year, I wouldn't expect Duran's WPA to continue to be that much higher than his WAAadj.  Still, if you check the most dominant relievers, most tend to have higher WPAs than WAA+WAAadj for their careers, which to me suggests that the leverage adjustment does not actually capture the true value of a dominant reliever in the highest leverage situations.  Mariano Rivera for example has a 32.5 WAA and 10.1 WAAadj for his career--42.6 total.  His WPA for his career is 56.6, so 14 wins better, increasing his career WAR to around 70, passing a bunch of HOF starters.  While Rivera was good enough as a reliever that his WAR actually does compare favorably to many starters, I think the adjustment using WPA feels more true to just how good he actually was.

1 minute ago, 2wins87 said:

Something of a side note that has been on my mind: I think the value of a truly dominant reliever isn't always fully appreciated anyway.  WAR calculations try to adjust for leverage, but I'm not convinced that they do enough.  BR, for example, has the leverage adjustment WAAadj.  According to them Duran's WAAadj was 0.4, his WAA (wins above average) was 1.8, and his WAR was 2.8.  However, his WPA was 4.6.  To get a different measure of his value to the Twins last year, my quick adjustment is to subtract WAA and WAAadj from WAR, and then add WPA, so 2.8 - 1.8 - 0.4 + 4.6 = 5.2 wins above replacement. Way above any of their starters and up there with Carlos Correa.

WPA is very noisy and not very predictive from year to year, I wouldn't expect Duran's WPA to continue to be that much higher than his WAAadj.  Still, if you check the most dominant relievers, most tend to have higher WPAs than WAA+WAAadj for their careers, which to me suggests that the leverage adjustment does not actually capture the true value of a dominant reliever in the highest leverage situations.  Mariano Rivera for example has a 32.5 WAA and 10.1 WAAadj for his career--42.6 total.  His WPA for his career is 56.6, so 14 wins better, increasing his career WAR to around 70, passing a bunch of HOF starters.  While Rivera was good enough as a reliever that his WAR actually does compare favorably to many starters, I think the adjustment using WPA feels more true to just how good he actually was.

I'm pretty convinced the WAR leverage index is overrating relief pitchers and WPA is a useless garbage stat like GWRBI.

2 hours ago, DJL44 said:

I'm pretty convinced the WAR leverage index is overrating relief pitchers and WPA is a useless garbage stat like GWRBI.

What makes WPA garbage?  It is a lot more sophisticated than game winning RBIs.

Why do you think leverage adjustments overrate relievers?  It already takes into account chaining.  The biggest single season adjustment I've seen is about 1 win, and typically it's only a few tenths.  It's usually not a very big adjustment.

3 hours ago, DJL44 said:

Duran's stuff is miles ahead of Lopez. If the Twins try Duran as a starter and it doesn't work out they can always move him right back to the bullpen. If it does work out they could have an ace at a minimum salary. It is hard for me to believe that they don't even want to try, especially since Duran wants to be a starter. It could be the team's biggest waste of talent since they released Luis Tiant.

The danger is that starting Duran may work until he is injured. Then the Twins have no starter and have lost the best reliever in the game today.

Pitchers making the move from starting to relieving pick up several MPH because they know they aren't pacing themselves or saving anything for later. Rocco was very vigilant about keeping him fresh, only pitching him back-to-back five times, and yet two of those second games resulted in a HR. Further, he only allowed 6 HR all year and the other four all came on or before May 5 when he was still settling in. 

And be honest about what he was doing as a starter in the minors: his best year was a 3.23 ERA at High A in 2019 when he was 21. He was still only throwing 5 innings a game and he was not blowing the league away, or even his teammates since the Ft Meyers team ERA that season was 3.11. 

Finally there is a difference in how pitching works when you only plan on facing a handful of guys. There was a good article on 538.com a few years ago that compared individual pitchers who had moved through starting and relief roles and compared their performance on the appearance length. https://fivethirtyeight.com/features/relievers-have-broken-baseball-we-have-a-plan-to-fix-it/  Basically it says that when you go to a one inning role your velo picks up, strikeout percentages go up, and you can throw your third pitch a lot less often.  Conversely, there's a big correlation between batters faced and strikeout rate (starting at the peak of around 4.5 BF) where the K% rate plateaus starting around 8.5 BF.  

1 hour ago, 2wins87 said:

What makes WPA garbage?  It is a lot more sophisticated than game winning RBIs.

Why do you think leverage adjustments overrate relievers?  It already takes into account chaining.  The biggest single season adjustment I've seen is about 1 win, and typically it's only a few tenths.  It's usually not a very big adjustment.

Picture two relievers. One strikes out the 3, 4, 5 hitters in the bottom of the 8th when the team is behind by 5 runs. The team rallies and goes ahead by 1 run in the 9th. The next reliever walks the 6, 7, 8 hitters and gets #9 to line into a triple play to end the 9th. WPA would have you believe the 9th inning reliever did a better job than the 8th inning pitcher. WPA doesn't address fielding at all which means it is ignoring people who actually prevented or allowed runs (1/3 of the value assigned by WAR) and assigns all the value to the pitcher and the hitter. Just by ignoring fielding is it overestimating the value of the pitcher by at least 50%. It is a storytelling stat, not one that is useful to determine value.

WAR awards leverage for circumstances out of the control of the pitcher but it doesn't address degree of difficulty. It is much more difficult to pitch 6 innings than it is to pitch 1 inning. The only reason the manager has the option to put a reliever in a high leverage situation is the starter was able to get them to that point in the game.

I think leverage is a good way to determine whether a manager is using his bullpen correctly but it doesn't tell us anything about the effectiveness of a pitcher.

1 hour ago, tarheeltwinsfan said:

The danger is that starting Duran may work until he is injured. Then the Twins have no starter and have lost the best reliever in the game today.

The exact same risk exists with him pitching max-effort out of the bullpen. The only way to avoid injury risk is to keep him from pitching.

Injuries happen when you're pitching tired, and you get tired by pitching too much on one day or too many days in a row.  Rocco has proven he can manage the relief load and the outcome was far superior to the results Duran saw as a starter. Let it ride.

2 hours ago, DJL44 said:

The exact same risk exists with him pitching max-effort out of the bullpen. The only way to avoid injury risk is to keep him from pitching.

I do not have any evidence to prove that a pitcher is less likely to be injured by pitching in relief rather than starting the game as a starter. However many have posted that the Twins do not want to risk moving Duran to starter from reliever. I wonder if this is true.

3 hours ago, DJL44 said:

Picture two relievers. One strikes out the 3, 4, 5 hitters in the bottom of the 8th when the team is behind by 5 runs. The team rallies and goes ahead by 1 run in the 9th. The next reliever walks the 6, 7, 8 hitters and gets #9 to line into a triple play to end the 9th. WPA would have you believe the 9th inning reliever did a better job than the 8th inning pitcher. WPA doesn't address fielding at all which means it is ignoring people who actually prevented or allowed runs (1/3 of the value assigned by WAR) and assigns all the value to the pitcher and the hitter. Just by ignoring fielding is it overestimating the value of the pitcher by at least 50%. It is a storytelling stat, not one that is useful to determine value.

WAR awards leverage for circumstances out of the control of the pitcher but it doesn't address degree of difficulty. It is much more difficult to pitch 6 innings than it is to pitch 1 inning. The only reason the manager has the option to put a reliever in a high leverage situation is the starter was able to get them to that point in the game.

I think leverage is a good way to determine whether a manager is using his bullpen correctly but it doesn't tell us anything about the effectiveness of a pitcher.

I agree that the lack of defensive accounting is an issue for WPA, but it doesn't systematically over value pitchers. Everything is measured from average. If a pitcher gets above average defensive plays behind him he will probably be overrated by WPA, but in the aggregate things even out.

For an individual outing, WPA vs performance can vary widely based on the luck of situations, sure. Given enough outings everything that is just luck should cancel out. That's kind of the whole idea behind WAR. We don't need to add up every little contribution to understand a player's overall contribution, we can use aggregate stats instead, and come up with a more stable estimate of true talent that way too.

Over a long enough period, Wins above average and WPA should theoretically measure the same thing. WPA is noisy, so I don't even think that a full career is necessarily long enough to say it is completely "accurate", but it should be long enough to eliminate most of the noise.

Every stat is a storytelling stat at the level of an individual event. But they become statistics when the events are repeated over and over.

WAR does address the degree of difficulty of starting too. Both at Fangraphs and BR the replacement level ERA is higher for starters than for relievers.  So before any leverage adjustment, starters are valued higher on a per inning basis for the same performance.

And no, of course leverage doesn't tell you anything about the performance of a pitcher, but it does, almost by definition, tell you how much of an effect that performance is likely to have on the outcome of a game.

1 hour ago, 2wins87 said:

For an individual outing, WPA vs performance can vary widely based on the luck of situations, sure. Given enough outings everything that is just luck should cancel out.

Given enough outings, it mostly measures the inning the pitcher was used in.

15 hours ago, MTV said:

He had injury concerns as a starter and I think he’ll have Jorge Lopez syndrome: a lights-out reliever or a 5.00 ERA starter, and I think everyone will pick the former.

His best seasons came when he pitched more innings.  His only real injury concern was in 2021 after not pitching at all in 2020.  The only season he had an ERA of 5.00 was a season in which he pitched 16 innings.  In the end it matters not what you think or what I think.  But at the end of the day if we don't take a chance we'll always be left with doubt.

As much as I’d like to see Duran start and win  12+ games, I’d rather see his durability improve to where he can save 30 games and still do it on a days rest which means the team scoring more runs so there are more low leverage days he doesn’t have to pitch.