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PHILADELPHIA -- By now, Phillies fans likely know that ace Zack Wheeler will miss the remainder of the 2025 season after being diagnosed with venous thoracic outlet syndrome (TOS).
The focus, rightfully so, is on Wheeler’s health first and foremost, but there are still plenty of questions to sort through.
What exactly is TOS? What’s the long-term outlook for Wheeler? How about the short-term impact on the Phillies? Could Wheeler’s absence open the door for top prospect Andrew Painter?
Let’s try to cover it all in one place …
What type of TOS is it and why does that matter?
The distinction between venous TOS and neurogenic TOS is an important one. Wheeler has venous TOS, meaning it involves compression of the veins and leads to symptoms such as heaviness due to a blood clot -- as he experienced last weekend in D.C.
This type of surgery comes with a recovery timeline of six to eight months. Of course, every case is different, but Rangers pitcher Merrill Kelly underwent this procedure in September 2020 and was ready for Spring Training in ’21 with the D-backs.
Neurogenic TOS, however, involves compression of the nerves, leading to symptoms such as numbness or tingling in the arm or hand. That’s the version that derailed Stephen Strasburg’s career.
The fact that Wheeler’s isn’t related to a nerve issue is encouraging. It’s also a positive that this wasn’t something that had been lingering, but instead “was more of an acute issue,” per Phillies head athletic trainer Paul Buchheit, meaning it appeared suddenly.
“If you have symptoms from a neurological perspective, they may be present for a long time and it takes a while to kind of evaluate and treat through,” Buchheit said. “A lot of times, you don't go to a surgical option right away. With Zack, it was an acute onset, so he doesn't have that long protracted time period where he's been battling things.
"The surgeons say that he's going to have a really good prognosis with this."
How might this impact Wheeler’s career?
The Phillies expect Wheeler to return for most, if not all, of next season. They also are hopeful that he will still be the perennial Cy Young contender that he’s been since arriving in Philadelphia in 2020.
"We figure that he'll come back in the 6-8-month time period and be the Zack Wheeler of old," president of baseball operations Dave Dombrowski said. "That's what we've been told. Unless something unanticipated happens, he'll be able to come back and pitch like he has before this."
Wheeler turns 36 next May. He’s under contract through the 2027 season, at which point he’s suggested he plans to retire. He’s long been open about wanting to win a Cy Young Award and a World Series title before walking away.
What are the Phillies’ rotation plans?
Over the past few weeks, manager Rob Thomson had said the club planned to deploy a six-man rotation once Aaron Nola was healthy. The idea was that everyone in the rotation could benefit from some extra rest down the stretch, especially with the Phillies in the midst of a stretch in which they’re playing 39 games in 41 days.
That plan was foiled when Wheeler landed on the IL one day before Nola returned.
Asked if the team had alternate plans for a six-man rotation in Wheeler’s absence, Thomson said it would be difficult at the current time because of the lack of flexibility in the bullpen. Basically, none of the team’s current low-leverage relievers have any Minor League options remaining, meaning the Phillies would need to DFA someone to call up a sixth starter.
That said, rosters expand next Monday, when teams are allowed to carry two extra players for the remainder of the regular season.
Could that be an opportunity to pivot to a six-man rotation?
“Possibly,” Thomson said. “Because we will have some flexibility then.”
Which brings up the obvious question …
Does this impact Andrew Painter’s status?
It seemed almost certain that Painter -- the Phillies’ top prospect and the No. 2 pitching prospect in baseball -- would make his debut this year. That is suddenly no longer a guarantee with the 21-year-old struggling with Triple-A Lehigh Valley, where he has a 5.11 ERA in 18 starts.
But given the benefits of a six-man rotation and the available roster spots starting next week, it might be worth giving Painter a look. The velocity and movement have been there on his pitches, he’s just struggled with control at times.
Maybe a callup would provide a spark. Maybe he would benefit from working with catcher J.T. Realmuto.
Either way, the Phillies have managed Painter’s workload in a way that he’s fully available the rest of the season, whether that’s in Philadelphia or Lehigh Valley.
“We planned it out so he can go the rest of the season and just be a normal pitcher,” Thomson said.
How much will Wheeler be around the team?
Wheeler is expected to undergo his surgery in the coming weeks. Though he obviously won’t be able to play, the hope is that Wheeler will still be around the team for its potential playoff run.
“I hope so,” Thomson said. “I haven't talked to him about that. I'm sure he will because he'll have some rehab to do. Whether he's here every day or not, I don't know yet.”
Some may recall the special moment prior to Game 1 of the 2023 NL Wild Card Series, when an emotional Rhys Hoskins received a massive ovation when he threw out a ceremonial first pitch despite being sidelined the season by a torn ACL.
Of course, there are plenty of factors to consider when it comes to Wheeler.
The top priority is obviously undergoing the surgery and beginning the recovery process. Once that’s taken care of, there will likely be restrictions on activities such as flying for up to a month after surgery.
Even when it comes to home games, there is plenty to consider. Given that Wheeler will likely be on blood thinners, just sitting in the dugout during a game could pose a risk if he were to be struck by a foul ball.
“Like we've always said, it's more about getting him healthy in general and not worrying about baseball health,” said teammate Kyle Schwarber. “We want him to be 100% for his family and his kids, and not feel like he's going to have anything to worry about as life goes on.”