The Houston Astros continue to be snakebit as shortstop Jeremy Pena and starting pitcher Tatsuya Imai both were placed on the injury list Monday.
Pena has a Grade 1 right hamstring strain, while Imai was sidelined because of arm fatigue.
Pena, who is batting .256 with five runs scored this season, said his knee tightened up during Friday's loss to the Seattle Mariners, but he finished the game. He tried to play Saturday but exited in the fourth inning and got imaging on Sunday.
He made his first All-Star team last year, when he batted .304 with 17 home runs, 62 RBIs, 20 stolen bases and an .840 OPS in 125 games.
Imai said he felt fatigued after throwing just 37 pitches in Friday's start against Seattle, getting one out. He returned to Houston on Saturday to be examined by team doctors.
Houston's starting rotation has been put through the wringer on its 10-game trip, during which the Astros have gone 1-8 heading into Monday's series finale with the Mariners.
In addition to Imai, the Astros placed right-handers Hunter Brown and Cristian Javier on the injured list last week because of shoulder strains. In addition, starter Cody Bolton left Sunday's loss in the second inning because of mid-back tightness.