Starting pitching has been the key to the Phillies' success. Their 14.3 fWAR from their starters is the third-best in baseball this year. Ace Cristopher Sanchez leads the way at 5.4 fWAR, while fellow southpaw Jesus Luzardo isn't far behind at 4.9.
With 2.6 fWAR, Zack Wheeler ranks third among the team's staff. Missing the first month of the year recovering from venous thoracic outlet syndrome, he initially didn't miss a beat. In his first 16 starts post-injury, he looked like the Cy Young candidate the team grew accustomed to:
2.16 ERA
2.89 FIP
30.8 K%
5.8 BB%
.185 batting average against
Since a dominant outing against the Dodgers on July 21 , it's been a downward spiral. Wheeler is mired in one of the worst stretches of baseball in his career. In six starts since that performance, he's posted an unsightly 8.51 ERA. Usually durable, he's not thrown more than five innings in any start ( a rain delay impacted one of his starts). While Aaron Nola and Andrew Painter have found their stride again, the Phillies need Wheeler back at the top of his game. But what has gone wrong for him over the last month?
Solid control has been a staple of Wheeler's career. Since 2018, Wheeler has never finished a season with a walk rate above 7.5%. For his career, he owns a flat 7% rate. That has become an even stronger trait since signing with the Phillies. In his first six seasons in Philadelphia, his walk rate has only been above 6% once (2024, 6.6%). This year's 7.6% mark is a little higher than his time in Philly but in line with career norms. How he's gotten to this point, however, has been far from even.
As mentioned earlier, his walk rate during his first 16 starts was just 5.8%. Wheeler's 43.1 Zone% (a stat measuring the percentage of pitches batters see in the strike zone) was just below the MLB average of 47.5%. He made up for that deficiency by getting batters to chase pitches outside the zone more often. His 35.9 O-Swing% (percentage of swings on pitches outside the zone) cleared the league average 30.3% clip.
Those numbers have sharply regressed in his last six outings . His walk rate has jumped to an uncharacteristically high 13.4%, and his Zone% has dropped to 39.7%. Batters have begun to be more patient and wait out close pitches, leading to his O-Swing% falling to 33.8%.
Much of Wheeler's successful work has been when he's working in the shadow zone. Defined as the area around the edges of the zone, Wheeler had a 42.1 S-Zone% during his best run this year. Batters swung 61.8% of the time at pitches in this zone from Wheeler. By working that part of the zone, it was harder for hitters to get a good pitch to barrel up.
Wheeler's ability to work well around the edges of the zone made it tough for batters to square him up. Sure enough, his batted ball data from the beginning of the year showed how he had found his success:
86.3 average exit velo
5.9 Barrel%
33.9 HardHit%
46.0% groundball rate
Recently, though, his shadow zone rate and swing rate at those pitches have dropped notably. His S-Zone% fell to 40.7%, while the swing rate at those pitches plummeted to 53.9%. With batters waiting for better pitches from Wheeler, the quality of opponent contact has gone up significantly:
89.9 average exit velo
8.5 Barrel%
43.7 HardHit%
36.6% groundball rate
A couple of specific games in this recent stretch showcase his struggles. However, his most recent outing against the Mariners shows a bit of everything at its best. Wheeler needed 103 pitches to get through four innings. In that time, he allowed four home runs and walked five batters, allowing eight runs on the day total.
The good news for the Phillies is that Wheeler isn't dealing with any injuries. He also hasn't seen any major drops in velocity, either, still sitting around the mid-90s with his fastball. Wheeler has already proven successful this year, so he has a blueprint to follow.
Wheeler's main goal will be to get his control back. That comes not just from limiting walks, but also from locating his strikes better. It's not a coincidence that earlier in the year he limited hard contact more when he stayed around the edges of the zone. But by staying around the edges, that'll also force batters into swinging more often.
Most important, he'll need to find a way to make his fastball effective again. Statcast 's Pitch Type Value/100 measures a pitch's runs above average per 100 pitches, allowing for more even judgment. Wheeler's fastball (wFA/C) and sinker (wSI/C) during his first 16 starts graded out at 1.88 and 2.15, respectively. Since then, they've fallen to -4.22 and 0.91, with his fastball grading as the worst of his arsenal. Regaining some life on his fastball specifically should help him even out his numbers a little more.
Wheeler has struggled before, but he's proven he can overcome it. Questions arose about how he would return from injury, but he responded by being his usual dominant self. While there's reason to be concerned now, he's shown that he can never be counted out, either.
The post Zack Wheeler's Struggles Are Concerning for the Phillies appeared first on The Lead .
