Chad Green got demoted, and it’s okay. He wasn’t demoted in a typical baseball sense, as in on a bus to Scranton/Wilkes-Barre. He got moved down a notch on the Yankees’ bullpen totem pole, in favor of surging Dellin Betances.
While Aroldis Chapman and David Robertson’s usage have remained relatively similar throughout the season, Green has been in high leverage spots less often. Meanwhile, Betances’ high leverage usage has gone up.
Betances has been pitching wonderfully of late (0 ER, 45.4 K% in last 14 IP), which explains half of the reasoning behind this shift. Green has been by no means a bad pitcher; his ERA is up to 2.17 (from 1.83) and his K% is down to 34.9% (from 40.7%).
So to be fair, by his own lofty standards, Green has been not great. Does that warrant this quasi-demotion? His stuff has certainly not diminished. The velocity on both his fastball and slider is up a tick.
Something weird is going on with Green, though. It became apparent, at least to me during his outing in Tampa Bay. on June 24th against the Rays, Green threw 35 pitches, exactly one of which was a slider. This is nothing new either, Green’s slider usage is down across the board in 2018. Even Chapman, who has one of the best fastballs in the game today, throws his slider more often.
Green isn’t throwing his slider less for no reason. According to FanGraphs’ pitch values, his slider has been worth -4.8 runs. For reference, it was worth 3.4 runs all of last season. His fastball is on pace to be just as valuable as last season, but no one pitch can be evaluated in a vacuum. A pitch is effected by the others that surround them in sequence.
So Green’s slider being worse will effect the rest of his repertoire, mainly his fastball. The only thing that can fix his slider is time — and maybe an adjustment or two. Believe it or not, high leverage situations late in games are not the best time to be tinkering with one of your pitches.
The Yankees are thus trying the same strategy they employed with Betances earlier in the season. Letting him work through the issues he was having with his breaking ball in low leverage situations, which clearly worked.
Losing Green in high leverage spots might hurt in the short term, but the Yankees’ bullpen is very good. I am confident that the trio of Chapman, Betances, and David Robertson can pick up any slack for now.
In the long term though, if this strategy works as it did with Betances, the Yankees will have four elite bullpen arms. When Tommy Kahnle returns they will have completed their bullpen Voltron and be well equipped to take on the postseason.