One day after losing 2019 American League Rookie of the Year Award winner Yordan Alvarez for the rest of the season with a right knee injury that will require surgery, the Astros were dealt another blow Thursday when All-Star third baseman Alex Bregman was placed on the 10-day injured list after suffering a strained right hamstring.

In a corresponding move, left-handed pitcher Cionel Pérez was called up from the alternate training site.

Bregman injured his hamstring running to first base in the fourth inning of Wednesday’s 13-6 win over the Rockies at Coors Field, and he immediately left the game. Astros manager Dusty Baker said Bregman was set to fly to Houston on Thursday to undergo an MRI. There’s no timeline for his return.

“We’re being very cautious with him because he’s had it before,” Baker said.

Hamstring injuries are nothing new for Bregman. He strained his right hamstring last April and missed two games. In September 2016 -- at the end of his rookie year -- Bregman missed two weeks after straining his hamstring running the bases. Baker said he could tell when Bregman left Wednesday’s game that he was in a lot of pain.

“He was walking out, and he was yelling going up the tunnel,” Baker said. “We all felt badly for him because he puts in the work. … We’re playing pretty good and by the time he comes back, we’re hoping we’ll make a move and overtake the A’s or anyone else in front of us. It’s disappointing. Every day we’re dealing with disappointment, but you’ve got to find a way to stay positive.”

In addition to Alvarez and Bregman -- who finished second in the AL Most Valuable Player Award balloting last year – the Astros lost 2019 AL Cy Young Award winner Justin Verlander (right forearm strain) after one start and 2019 AL saves leader Roberto Osuna (right elbow soreness) earlier this month. All-Star outfielder Michael Brantley (right quad) is on the IL but should be activated Saturday in San Diego.

Bregman was hitting .272 with four homers and 14 RBIs, and he was riding a nine-game hitting streak following his double on Wednesday. He has reached base in 40 consecutive games, which is the longest active streak in the Major Leagues.

Abraham Toro started at third base on Thursday, but Baker said he expects to rotate players at the position. Jack Mayfield and Yuli Gurriel can also play third. Aledmys Díaz, who went on the IL after one game with a groin strain, figures to get most of the at-bats at third when he returns, but Baker said he’s not sure when that will be.

“You don’t want to rush him [because] you end up losing him, too,” Baker said.

Baker said Brantley was scheduled to work out with the trainers and third-base coach Gary Pettis prior to Thursday’s game in Denver. When he returns, he will split time between the outfield and DH, a position expected to be locked down by Alvarez before he suffered a knee injury and was scheduled for surgery next week.