"It was a no-brainer," Erstad said. "I got it pretty good, and unfortunately I've done this in the past. It's been about six years since I had a real problem with [hamstrings], and I thought I had them under control. You can't leave the team short for a week with the situation we're in."
Erstad, who is hitting .185 in 92 at-bats, was on the disabled list three times with hamstring strains or tendinitis in 2003 and '04 with the Los Angeles Angels of Anaheim. This is his first trip to the disabled list since he signed with the Astros prior to last season.
"It's definitely not something I'm super concerned about, but you just have to get through the two weeks here and be ready to go," Erstad said.
Astros general manager Ed Wade and manager Cecil Cooper spoke with Erstad following Saturday's game, and Wade touched base with Erstad again Sunday morning to gauge the severity of the injury.
Just as the Astros were preparing to take off and fly home from Los Angeles on Sunday night, head athletic trainer Nate Lucero informed Wade that Erstad believed the injury could keep him out a week to 10 days.
"At that point, I sent text messages to [assistant general managers] David [Gottfried] and Ricky [Bennett] to get Kata here for today," Wade said. "In defense of a guy like Darin, no matter how strenuously you prepare pregame, if you're not out there playing when the game starts, it's different.
"He stays ready and he's always ready to play, but I think you'd be more prone to those things occurring if you're not out there playing on a regular basis."
Kata, 31, was hitting .281 with two home runs and 14 RBIs for Round Rock. This will be his second stint with the Astros this season. He hit .182 in 22 games through parts of June and July.
Kata has appeared in five Major League seasons with Arizona (2003-05), Philadelphia ('05), Texas ('07), Pittsburgh ('07) and Houston ('09). He has a career .239 batting average with 12 home runs and 62 RBIs.
Brian McTaggart is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.