In a game that had precious few Yankee highlights, one of them last night was Caleb Cotham's MLB debut. As described in the recap, he pitched 1.2 scoreless innings and struck out 4 batters without issuing a walk. In doing so, he became the 12th different rookie pitcher the Yankees have used out of their bullpen this season and the 8th to make his Major League debut. That might seem like a sign of major performance/injury problems, but it really hasn't been the case. While there have been a few instances of that happening (see "Carpenter, David" and "Miller, Andrew"), the Yankees' strategy lately in shuttling guys up and down to fill out the back end of the bullpen has been mostly a proactive one. They know they need to have fresh arms available to cover for their rotation, they know they need to be able to give their bullpen regulars enough rest, and they know they have a stockpile of useful arms in Triple-A to help serve those purposes.
And how has this collection of fringe-y arms performed? Not too bad actually. Combine all the non-Chasen Shreve and Chris Martin - because they were on the Opening Day roster - pitchers together (Branden Pinder, Bryan Mitchell, Diego Moreno, Jacob Lindgren, Jose De Paula, Nick Rumbelow, Jose Ramirez, Matt Tracy, Dan Burawa, and Cotham) and you get this line:
50 IP, 46 H, 24 ER, 23 BB, 48 K (4.32 ERA)
Remove Ramirez and Burawa's 4 rough appearances and you get this:
46.1 IP, 37 H, 15 ER, 18 BB, 45 K (2.91 ERA)
That's pretty good value for the last spot in the bullpen. It's been mostly low-leverage work, there hasn't been too much of an impact of the outcomes of those games, and there have been some pretty good performances. Mitchell was lights out in short relief before getting sent back down, Pinder showed himself to be competent and capable, Rumbelow looked good in a small sample, and Moreno might have carved out a longer-term role for himself. Add in Shreve's 40+ innings of sub-2.00 ERA ball and the overall contribution of this rookie relief corps really looks solid.
The Yankees have always been good about finding under-valued relievers to take on chunks of workload and this year has been no different. What has been different is the way they've gone about doing it with their own internal cadre of pseudo-prospects, and they deserve credit for that. They've helped themselves manage workloads in the present and given themselves options to consider for the future. Not a bad way to manage the lesser-heralded part of your farm system.