HOUSTON -- Astros general manager Ed Wade said on Thursday that starting shortstop Clint Barmes, who's beginning the year on the disabled list with a broken bone in his left hand, could be back sooner than originally expected.

Barmes, who was expected to miss four to six weeks, was examined recently by team physician Dr. Tom Mehlhoff, who was "cautiously optimistic" that Barmes could return in three to four weeks. He was hit by a pitch on his hand on March 25.

"He was pleased with his grip strength," Wade said. "If he continues to make progress while we're gone, he can see him freed up to grip a bat when we get back. Hopefully, it moves a little bit faster than we had anticipated."

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Meanwhile, left-hander J.A. Happ, who left Tuesday's game in Oklahoma City with a strained right oblique, will throw a light bullpen session on Friday in Philadelphia and could still make his scheduled start on Sunday against the Phillies.

"Right now, there's still a possibility for Sunday," said Wade, who said Happ could be pushed back to Tuesday or even next Sunday without causing any upheaval in the rotation.

Mills has lineup in mind for opener

HOUSTON -- Astros manager Brad Mills gave a hint of what his starting lineup might look like for Friday's season opener in Philadelphia at 12:05 p.m. CT. Mills said on Thursday that the lineup the Astros used in Wednesday's exhibition against the Red Sox is likely his Opening Day lineup, sans the designated hitter.

The lineup Mills is leaning toward using is: Michael Bourn (center field), Angel Sanchez (shortstop), Hunter Pence (right field), Carlos Lee (left field), Brett Wallace (first base), Bill Hall (second base), Chris Johnson (third base) and the catching spot at eighth, which on Opening Day would be Humberto Quintero.

"That's pretty close to what it's going to be," Mills said. "I'm still going to look at some things [Thursday night] and in the morning, but that's pretty much it right there."

Mills doesn't expect many lineup deviations based on whether the Astros are facing a left-hander or a right-hander.

"We're pretty set with them, and as we move forward and we get a week, two weeks, a month in the season, there's going to be some changes there," he said. "I don't know what they are, but we'll have to see how the guys are responding to what kinds of seasons they're having."