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It is no secret the Yankees face some significant problems in the starting rotation following the trade deadline. General manager Brian Cashman had considered acquiring Jack Flaherty from the Detroit Tigers but opted out of a potential deal due to medical and value concerns.

The Yankees May Be Regretting Not Making a Move For a Starter

At this point, the Yankees likely would’ve made a move for a starter, given they foresaw the regression of both Marcus Stroman and Nestor Cortes. The Yankees do have Clarke Schmidt and Cody Poteet returning from injury, but can we really invest that much faith in Schmidt coming back from a multi-month hiatus to revive his season and put together above-average metrics?
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That seems like an optimistic ask, and the Yankees might have to temper their expectations a bit.

At the moment, they’re trying to do everything possible to rejuvenate, pulling him from his most recent start and giving him time to work on his mechanics.

Stroman’s Decline Has Been Steep

The 33-year-old veteran hosts a 4.10 ERA and 4.88 xERA. His numbers are regressing, including a career-low 6.65 strikeouts per nine and a 48.6% ground ball rate, the first time in his career that he has been below 50%. In addition, he’s walking the most batters in his career and giving up the most home runs, so it is evident that his stuff isn’t only marginally worse, but it is significantly down across the board.

Stroman has lost nearly 2 mph on his fastball, and his sinker is below 90 mph. There’s a legitimate concern that his arm may be giving out due to age and fatigue. The Yankees need to give him time, but it simply isn’t a mechanical issue; this is a physical problem. Stroman isn’t going to add 2 mph back to his fastball with a few mechanical changes; he needs time to rest, and that is what the team is providing.

As for Cortes, his velocity looks strong, but his accuracy and pitch movement aren’t getting the same results. Over 134.1 innings, Cortes hosts a career-low 8.31 strikeouts per nine, and while his walk rate is at a career-low, his 1.41 home runs per nine are problematic. All of his numbers are relatively within normal margins, but opposing batters are destroying his four-seam fastball, cutter, and sweeper. In fact, not a single one of his primary pitches has a batting average below .254.

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When it comes to Cortes’s pitch movement, his fastball has gained an inch of horizontal movement and even slightly increased in vertical movement. His cutter has lost a little bit of vertical movement, but nothing to write home about.

Nestor is Struggling to Execute

For the most part, Cortes is simply not locating his pitches as well and attacking with the right sequence. Batters are picking up on all of his stuff, and it could be due to a lack of velocity and familiarity with his game. Cortes made a living on unique deliveries and creative style, but that trend seemed to have lost some of its spunk, and the Yankees need to find a way to change things up.

In the end, both Cortes and Stroman rank among the league’s worst in multiple categories, including fastball velocity, average exit velocity, chase rate, and whiff rate. Stroman is known for his high-ground ball percentages, while Cortes ranks in the 4th percentile in that category. They’re different in a lot of ways, but they share one similarity: significant regression.

Based on the underlying metrics, Cortes is certainly more favorable for a resurgence, but if Stroman can add a bit of velocity back to his pitches, the Yankees may have to pull him out of the rotation at some point during games and likely can use him during the postseason.