Astros manager Dusty Baker is hopeful that designated hitter Yordan Alvarez can return to the lineup on Monday against the Rockies after right knee discomfort forced him out of the starting lineup in Houston's 3-2 walk-off win on Sunday.

Baker said he might have used Alvarez on Sunday against Seattle in the right spot as a pinch-hitter, though Alvarez has played in just two games since rejoining the team last week after a bout with COVID-19.

“He was supposed to be off today anyway because he hadn’t run that much [at the Astros' alternate training site],” Baker said.

That plan changed when Michael Brantley went on the 10-day injured list on Saturday with right quad discomfort. When Alvarez slid hard into third base on Saturday, Baker wondered how he’d feel Sunday morning. Turns out, not all that well.

“Hopefully, he’ll be all right [by Monday],” Baker said. “We’re just going to have to wait and see.”

Alvarez was bothered by sore knees on and off over the past two seasons, which forced a pause on the team’s plans for him to play the outfield at times. Alvarez also said he'd played with knee pain through much of 2019 when he unanimously won the American League Rookie of the Year Award after clubbing 27 homers in 87 games.

However, Alvarez said it was the left knee that bothered him last year after he fouled a ball off that area last season. That he now has issues with his right knee will be worrisome at a time when the Astros finally had their projected 2020 lineup on the field for the first time.

Alvarez homered in his first at-bat of the season after he was activated on Friday, and went 2-for-8 in his two games. He was on Baker's original lineup card Sunday morning, but was replaced by Abraham Toro about an hour before first pitch.

Around the horn
• The Astros called up infielder Jack Mayfield from their alternate training site to replace outfielder Michael Brantley, who was placed on the injured list with discomfort in his right quad.

• Astros rookie right-hander Cristian Javier entered Sunday's game ranked third among AL pitchers with a .153 opponents' batting average, having allowed 11 hits in 21 2/3 innings. He allowed the Mariners one hit in six shutout innings in Saturday's 2-1 victory. At 23, Javier's the fourth-youngest pitcher in club history to allow one hit or less in an outing of at least six innings.

• Martín Maldonado is first among AL catchers with 15 RBIs after going 1-for-3 on Sunday. That's the most by an Astros catcher in the first 21 games of a season. He also had his first stolen base since Aug. 5, 2016, and registered two caught-stealing plays against the Mariners. Not bad for a day's work -- especially on his 34th birthday.