The Houston Astros' injury woes deepened Monday as shortstop Jeremy Pena and starting pitcher Tatsuya Imai both landed on the injured list. Pena suffered a Grade 1 right hamstring strain, while Imai was placed on the shelf with arm fatigue. The timing couldn't be worse for a team already struggling on the road and desperately needing to get healthy.

Pena felt his knee tighten during Friday's loss to the Seattle Mariners but finished the game. He attempted to play Saturday but exited in the fourth inning and underwent imaging Sunday. The shortstop is batting .256 with five runs scored this season, a significant drop from his All-Star campaign last year when he hit .304 with 17 home runs, 62 RBIs, 20 stolen bases and an .840 OPS in 125 games.

Imai returned to Houston on Saturday for examination after throwing just 37 pitches and recording only one out in Friday's start against Seattle. The Astros' starting rotation has been decimated this road trip, with right-handers Hunter Brown and Cristian Javier already on the injured list with shoulder strains, and Cody Bolton exiting Sunday's loss with mid-back tightness. Houston entered Monday's series finale at Seattle with a dismal 1-8 record on their 10-game road journey, leaving their pitching staff severely depleted.