Houston Astros left fielder Yordan Alvarez. Erik Williams-USA TODAY Sports

The Houston Astros’ top power hitter is reportedly operating at less than 100 percent during the ALCS.

Ken Rosenthal of The Athletic reported Monday that Astros slugger Yordan Alvarez is dealing with a virus. Rosenthal says that Alvarez currently has an upset stomach and headaches, noting that the two-time All-Star was not part of introductions during Sunday night’s Game 1.

Alvarez was invisible during Houston’s 2-0 loss to the Texas Rangers to open the ALCS. He went 0-for-4 and struck out three times. The turnaround does not get much more forgiving from here either as Game 2 of the series is already on Monday afternoon.

An under-the-weather Alvarez is bad news for the Astros since he led the team during the regular season in homers (31), on-base percentage (.407), and slugging percentage (.990), all despite playing in just 114 games. Alvarez also absolutely raked during the ALDS against Minnesota with four homers and six RBIs in Houston’s four-game victory.

The 26-year-old Alvarez is still listed in the lineup for Monday’s game. But with the Astros already a bit shorthanded, they now face even more of an uphill climb to avoid going down 2-0 in the series before it shifts over to Arlington.

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