As it stands, Matsui is not available for the remainder of the Chicago series. He's hoping to be ready for the series with the Rockies, which begins Friday in Colorado after a scheduled off-day.
"I'll have to see how I feel [Wednesday]," Matsui said. "Maybe the situation will be changed."
"He won't play [in Chicago]," manager Cecil Cooper said. "We're not going to push it. I'm hoping for [Friday]. Yesterday he was a little bit sore, so he probably needs a few more days."
Matsui has been on the disabled list since Aug. 13 with an irritated disc in his lower back. He has missed 49 games this year due to three different injuries.
Teams were permitted to expand their rosters to a maximum of 40 on Sept. 1, so the Astros did not need to clear a space on their 25-man roster in order to make room for Matsui. Therefore, even though Matsui won't be ready to play for a few more days, Cooper saw no reason to keep the second baseman on the disabled list.
"He's going to be activated, anyway," Cooper said. "Might as well do it. He's on the 40-man roster, anyway. Why not today? It could have been yesterday, too."
In other injury news, right-handed reliever Geoff Geary hasn't pitched since Aug. 26, due to recurring pain near his right groin. As for a projected return date, Geary said simply, "hopefully, Colorado."
Realistically, however, Geary probably won't be cleared to pitch until the team returns home to host the Pirates on Monday. He may throw a bullpen session some time during the Rockies series, possibly Friday.
Geary spent 16 days on the DL with a strained right groin from May 16 to June 3.
Alyson Footer is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.