Philadelphia Phillies ace Zack Wheeler was cruising toward another star season, but his roll was stopped dead in its tracks when he was diagnosed with a blood clot in his right upper arm.

The seasoned pitcher, who has been one of the most dominant hurlers in baseball since 2020, officially confirmed on social media, thanking Phillies fans for their immense backing. It was really a difficult season for Wheeler.

Zack Wheeler to Undergo Surgery After VTOS Diagnosis

Zach Wheeler Reveals He's Undergoing Surgery Following Venous Thoracic Outlet Zach Wheeler Reveals He's Undergoing Surgery Following Venous Thoracic Outlet
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According to Essentially Sports, Wheeler's condition was diagnosed by doctors as venous thoracic outlet syndrome (VTOS), a squeezed vein between the collarbone and ribs. Unlike the more complicated neurogenic type of TOS, the venous type has a better prognosis for recovery.

The problem, however, needed to be addressed right away, effectively ending Wheeler's 2025 season.

Medical professionals are also hopeful, estimating that Wheeler will take six to eight months to recover. It was recently compared to the recovery of Merrill Kelly, who successfully recovered from a similar prognosis.

The timeline keeps Phillies fans optimistic that Wheeler may become his ace self before the start of the 2026 season.

Wheeler's Absence Could Mean a Lot For the Phillies

Per Fox29, the loss of Wheeler is a crushing blow to the Philadelphia Phillies' postseason chances. Since 2020, the right-hander has recorded 1,094 strikeouts with a 2.91 ERA, proving his status as one of the league's most reliable pitchers.

His postseason numbers are even more impressive, with a career 2.18 ERA in playoff appearances, making him a proven weapon in high-pressure games. Without their ace, the Phillies have to get through a tough stretch, not just tactically, but from a morale standpoint.

Phillies Rotation Adjustments

In his place, the Phillies' rotation must be immediately reshuffled. Cristopher Sanchez will be slotted into the Game 1 role, with Ranger Suárez and Jesús Luzardo serving as lefty depth. Having Aaron Nola return in the righty starter role brings balance, but it will take stability from the entire rotation to stay in the mix.

As well, ace prospect Andrew Painter might be summoned, providing the Phillies with more flexibility while maintaining an eye on long-term viability. Handicapping starter health, bullpen usage, and playoff preparedness will now be the organization's greatest challenge.

Though Zack Wheeler's 2025 season is cut short, the Phillies are still hopeful that they will bounce back without one of MLB's best pitchers. Though the path to October has just grown immensely steeper, it's only a matter of time before they figure out the best rotation to fit the adjustments.