Houston Astros starting pitcher Lance McCullers Jr. Matt Marton-USA TODAY Sports

Astros starter Lance McCullers Jr. left his final start of the club’s AL Division Series win over the White Sox after four innings due to some tightness in his forearm. Jon Heyman of the MLB Network now reports (Twitter link) that McCullers is likely unavailable for the upcoming American League Championship Series against the Red Sox, which is scheduled to begin on Friday. However, Bob Nightengale of USA Today reports that he might be able to return for the World Series, should the Astros advance.

It doesn’t seem to be a long-term concern, as Heyman reported Thursday morning that an MRI suggested McCullers “should be fine in the long run.” That aligns with the pitcher’s initial assessment of the injury, as he told reporters on Tuesday that he didn’t believe the issue to be related to his ligament. McCullers missed the entire 2019 season recovering from Tommy John surgery.

Given that injury history, it’s no surprise the Astros are expected to play things cautiously with McCullers over the coming days. He remains a vital part of the franchise’s long-term future, having signed a five-year, $85M extension in March that’ll take effect beginning in 2022.

Still, his (presumed) absence will be felt over the upcoming series, as McCullers is arguably the Astros’ top pitcher. This season, he worked 162 1/3 innings of 3.16 ERA/4.01 SIERA ball. As he typically does, the righty posted well above-average strikeout and ground-ball rates (27% and 56.4%, respectively). That offset an elevated 11.1% walk percentage to allow McCullers to post the fifth sub-4.00 ERA season in his six-year MLB career.

In McCullers’ absence, Houston looks likely to turn to some combination of Framber Valdez, Luis Garcia, José Urquidy and Zack Greinke to start against Boston. Jake Odorizzi was a healthy scratch for the Division Series, although he could be brought back onto the ALCS roster in McCullers’ place to offer an additional starting and/or multi-inning relief option.

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