TINSTAAPP is an (albeit clunky) acronym coined by Baseball Prospectus many years ago, and has been frequently thrown around by analysts as a cautionary note. It stands for "There Is No Such Thing As A Pitching Prospect," and refers to the frequency with which promising young hurlers fizzle out by the time they reach the major leagues.
That truism should certainly be kept in mind as we run through some of Minnesota's outstanding performers in the minors – nothing is close to guaranteed with any of them – but that's why the sheer volume of intriguing names is so encouraging.
Here's a snapshot of the club's best pitching prospects, and a review of what they've been able to accomplish this year.
1. Jose Berrios, RHP, Class-AA Chattanooga
2015 Stats: 50.0 IP, 4-2, 2.88 ERA, 58/16 K/BB, 1.16 WHIP
ETA: Late 2015
That Berrios has demonstrated such dominance is made all the more impressive by the fact that he won't turn 21 for another week, making him younger than all but one position player in the Southern League. He's going up against older and more experienced hitters and blowing them away. Berrios has a pretty good case as a Top 5 pitching prospect in all the minors right now.
2. Stephen Gonsalves, LHP, Class-A Cedar Rapids
2015 Stats: 36.0 IP, 3-1, 1.75 ERA, 47/7 K/BB, 0.83 WHIP
Gonsalves ranked 13th on our preseason listing of top Twins prospects. When I profiled him, I marveled at his tremendous projectability as a 6'5" lefty with improving velocity and noted the following: "If he can put in a full season and maintain his performance in High-A, he'll surely vault into the Top 10 next year and maybe the Top 5." The 20-year-old returned to Cedar Rapids, where he finished last year with eight excellent starts, and has taken his game to another level as illustrated by his ridiculous K/BB ratio. Presumably, he'll be in Ft. Myers within a couple of weeks.
3. Chih-Wei Hu, RHP, Class-A (Advanced) Ft. Myers
2015 Stats: 35 IP, 4-0, 1.03 ERA, 36/6 K/BB, 0.83 WHIP
ETA: Late 2016
Hu wasn't a high-profile acquisition when the Twins brought him in as a teenager from Taiwan in August of 2012, signing for a relatively modest $220,000. But while it's early, he's shaping up as one of the franchise's biggest successes ever on the international market. His absurdly good numbers in Ft. Myers would be easier to pass off as a fluke if they weren't exactly in line with what he did in Low-A and rookie ball the past couple years. When you hear the term "command-control guy" you might be tempted to affix a low ceiling, but Hu can reach the mid-90s with his fastball and has tallied strikeouts steadily at every level. He has also allowed only one home run in 148 pro innings. The Twins showed how highly they thought of him when they called him up to make a spot start in the first leg of a Triple-A doubleheader on Tuesday. Hu rose to the challenge with six innings of one-run ball, picking up the win and pushing his career record in the minors to 15-2.
4. Alex Meyer, RHP, Class-AAA Rochester
2015 Stats: 34.2 IP, 2-2, 7.02 ERA, 34/21 K/BB, 1.87 WHIP
ETA: Late 2015
Obviously, Meyer doesn't belong in the same conversation as the three names listed above based strictly on 2015 numbers, but his ability and his history cannot be ignored. After competing for a spot on the major-league roster in spring training, the righty reported to Rochester where he's been battling through the toughest stretch of his pro career. His mechanics are out of whack, his already shaky command has deteriorated, and he's uncharacteristically giving up tons of hits. As ugly as things are right now, you have to believe that eventually the 25-year-old will get it straightened out and remind everyone why both MLB.com and Baseball Prospectus ranked him as a Top 30 prospect in baseball prior to the season.
5. Tyler Duffey, RHP, Class-AA Chattanooga
2015 Stats: 52.2 IP, 2-2, 2.56 ERA, 54/12 K/BB, 1.10 WHIP
Duffey is a former college closer but you wouldn't know it from his consistently strong numbers as a starter in the Twins' system. He has routinely pitched deep into games for Chattanooga this year, averaging nearly 6.2 innings per start, and has held opponents to a .236/.282/.338 slash line while – somewhat surprisingly – averaging more than a strikeout per inning. The Southern League is a tough environment for pitchers so the fact that Duffey is achieving the best results of his career there bodes well.
6. Kohl Stewart, RHP, Class-A (Advanced) Ft. Myers
2015 Stats: 27.2 IP, 0-3, 2.93 ERA, 14/11 K/BB, 1.37 WHIP
It hasn't been two years since Stewart was drafted No. 4 overall, and he has a 2.47 ERA in the minors, so it feels a little odd to have him ranked this low, but recurring injury problems and a disturbing lack of strikeouts have obscured his outlook. Since moving up to full-season ball, the righty has managed only 78 strikeouts in 114 innings (6.0 K/9) – perplexing for a pitcher of his elite pedigree. The good news is that he has managed to keep opposing bats quiet even without missing them, allowing only 115 hits and four homers in 134 pro innings. If he can get healthy and start dominating he'll climb very fast.
7. Taylor Rogers, LHP, Class-AAA Rochester
2015 Stats: 49.0 IP, 3-2, 3.31 ERA, 44/18 K/BB, 1.31 WHIP
ETA: Late 2015
A young left-handed pitcher who has succeeded everywhere and has seen his K-rates rise as he's ascended the minors? Sign me up! Rogers is similar to Duffey in that his game is more polish than power, and like many southpaws he'll need to figure out how to handle righties to stick as a starter (they've got an .867 OPS against him this year despite his overall success) but Rogers is going to pitch in the big leagues – quite possibly before anyone else on this list.
8. Felix Jorge, RHP, Class-A Cedar Rapids
2015 Stats: 36.1 IP, 1-2, 1.98 ERA, 37/7 K/BB, 0.97 WHIP
The Twins signed Jorge at age 17 out of the Dominican Republic for $250,000 back in 2011, and he immediately made a name for himself in the system with a couple of fantastic seasons in the rookie leagues. He lost some of his luster last year when he struggled immensely in his first exposure to full-season ball in the Midwest League, but now he has returned to Cedar Rapids and been spectacular. He's a wiry specimen, listed at 6'2" and 170 lbs, but if he can add a little to his frame while he grows he's got a chance to be a force.