A Relief Ace Rotation, Part 2: What Does A Relief Ace Rotation Look Like?

The Twins ought to prioritize re-signing Romo no matter what, but he’s an especially good fit for this kind of gig, so if they were to pursue it he’d become an even better target. They would pitch every third game. Almost every appearance for Rogers, Duffey, and Romo would thus come on either two or three days of rest.

Depending on the opposing lineup and the starter scheduled for that day, the day’s relief ace might serve as an opener, be called in immediately when the starter needs to be lifted, or saved for anywhere from three to eight outs at the end of the game. The point is that they would be given a firm schedule, with designated time for rest and recovery, a throw day to work on a given pitch or make mechanical tweaks, and the ability to game-plan for opposing teams and individual hitters in a more focused way.

Rogers showed the ability to work all the way through an opposing lineup within a game at times last year. He could do it semi-regularly under this system. Romo could be reserved for a segment of the opposing lineup loaded with right-handed batters, perhaps as an alternative to the starter facing that group a third time. As starters sometimes must, a relief ace might be asked to prepare differently from outing to outing, according to the path the team sees through the 27-out gauntlet of the contest. However, as a starter does, they would benefit from at least knowing in advance on which day they’d be asked to do so.

The loop would need to be three pitchers deep, because while one day of rest makes a huge difference relative to zero days under current usage patterns, a pitcher asked to throw roughly every other day would be on fumes by August. Three is the magic number here. It avoids both overrest and overwork, both in short windows and over the long season.

Involve more pitchers, by making a middle relief rotation for instance, and the staff might become too rigid. Unpredictable situations could demand that a team be ready to stretch a given pitcher out, or throw them on back-to-back days, and while a relief ace rotation can decrease the frequency of such incidents, a manager still needs flexibility further down the depth chart. Besides, there will always be some pitchers—Trevor May is an example, though far from the only one—who thrive on a less consistent usage pattern, finding rhythm and averting fatigue when working back-to-back games, and fluid roles should be held open for such players.

Let’s tackle the obvious objections here. First of all, yes: making this change would decrease the average leverage index of these pitchers’ appearances. Inevitably, it would mean that some percentage of Rogers', Duffey’s and Romo’s innings would end up being virtually meaningless. As currently constructed, bullpens concentrate the most important innings in the hands of the best few pitchers within them. This system would more evenly distribute those opportunities, and it could lead to more narrow leads being blown by the fourth or fifth arm in the bullpen.

It would fall to May, Zack Littell, Cody Stashak, and another two hurlers of even less distinction to build bridges from the starter to the designated relief ace of the day, or to close things down if the day’s ace pitched early. Like the Boston Red Sox’s closer-by-committee experiment of 2003, the plan would risk ridicule and a certain degree of clubhouse turmoil should it not go well right out of the chute.

However, there’s a case to be made that the existing system- especially the one that came into vogue early in the 21st century, wherein a good bullpen would have a formulaic hierarchy of three hurlers lined up behind a starter the team hoped would go six innings: set-up, set-up, closer- creates its own set of problems. A winning streak becomes oddly taxing, when a team has to call on its trio of dominant relievers five times each in seven days. If a manager elects to be cautious with those arms, that streak might never even materialize. Pitchers further down the ladder get fewer chances to demonstrate their own value, and just as importantly can suffer either rust or overuse when the team gets very hot or very cold.

With the depth the Twins will hope they still have come Opening Day, rotating relief aces to get the best possible performance from them doesn’t even cost that much. May, Littell, and Stashak, among others, can provide adequate work in medium-leverage middle relief.

There are other concerns and challenges, too, should the Twins proceed down this road. We’ll cover those in Part 3 tomorrow.

Here is Part 1 of this series.