Why Zack Wheeler can still thrive if his velocity doesn’t completely return

The next time Zack Wheeler pitches in a game, it will be for the Phillies on Saturday in Atlanta against the Braves. And even though Wheeler’s velocity didn’t impress during his five-start minor-league rehab assignment, there are reasons to believe he can still thrive with lesser velocity.

Wheeler’s final rehab assignment numbers were not great. He posted a 5.85 ERA and allowed 19 hits across 20 innings. He racked up 23 strikeouts to five walks. His velocity varied.

On April 14, Wheeler sat 92.5 mph to 95 mph against the Somerset Patriots at TD Bank Ballpark in his fourth rehab start, a minor-league source told Phillies Nation’s Ty Daubert. On Sunday, Wheeler faced the Patriots again, this time in 47-degree weather. Wheeler’s fastball sat in the low 90s, a source told Daubert.

Those velocities are not “normal” for Wheeler. He throws two fastballs: a four-seamer and a sinker. His four-seamer averaged 95.7 mph between 2023 and 2025. The sinker averaged 95 mph.

Wheeler threw 77 pitches in a four-inning, four-run performance Sunday.

“Considering how cold it was, I thought that was pretty good,” manager Rob Thomson said.

But nearing 36 years old and coming off major surgery — thoracic outlet decompression surgery to be exact — Wheeler’s velocity may not return, in the short- or even long-term. He should be fine either way.

Wheeler does rely heavily on his fastballs. Between ’23 and ’25, 60 percent of the pitches he threw were either a four-seamer or sinker. Hitters had a hard time against them. Velocity was certainly part of that.

Wheeler held opponents to a .211 batting average and .351 slugging percentage when throwing his four-seamer and sinker between ’23 and ’25 — very much above-average numbers. Against those pitch types, major league pitchers allowed a combined .263 batting average and .432 slugging percentage in that same time frame. Wheeler induced a 26.3 percent combined whiff rate when throwing his fastballs. The league average was 19.4 percent.

While Wheeler’s hard stuff is a main reason why he’s been one of baseball’s best pitchers since becoming a Phillie, he has developed an expansive arsenal that’s also been part of that equation. He throws six pitches. His secondary pitches are a sweeper, curveball, splitter and cutter. They are weapons.

Against Wheeler’s four secondary offerings, hitters had a .201 batting average and .340 slugging percentage between ’23 and ’25. Wheeler induced a combined 33.5 percent whiff rate with those pitches; league average was 29.1 percent. When batters made contact against Wheeler’s secondary stuff, it wasn’t the best.

Wheeler limited opponents to a 31.3 percent hard-hit rate and 6.4 percent barrel rate when throwing his secondary pitches over the last three seasons. Those were better than the combined league averages, which were 35 percent and 7.6 percent, respectively.

It is possible as Wheeler continues to get back into the swing of things his ability to sit in the mid 90s returns. He could get stronger. Warmer weather could also help. But, as some would say, the right-hander is a pitcher, not a thrower. He may not need his old velocity to have success.

Velocity has been important for Wheeler throughout his career. He has also become a more polished pitcher with the Phillies. If hitters get to his four-seamer and sinker more often because it doesn’t sit 94 mph to 96 mph, then he could increase the usage of his secondary stuff to counteract that.

And, if that’s the case, Wheeler’s performance could still be really good because that secondary stuff is so good.