HOUSTON -- Before Saturday's game, Astros manager Brad Mills told second baseman Jose Altuve that he'd better play hard because he would have the day off on Sunday.

Sure enough, the All-Star was out of the lineup for Sunday's game against the Brewers. Tyler Greene, acquired from the Cardinals on Thursday, started at second base and batted leadoff. Since the All-Star break, Altuve has only had one day off: July 20.

Mills isn't too concerned about Altuve wearing down going forward.

"He's played quite a few games straight and we've got a guy like Greeny that is able to plug in and do real well," Mills said. "We've got an off-day Thursday coming up, followed by an off-day on Monday. With those off days moving forward, I think that's fine."

Altuve made 625 plate appearances between the Minor Leagues and Major Leagues in 2011. Through Aug. 11 of last season, Altuve had 477 total plate appearances. Entering Sunday's game, Altuve has 470.

Since July 20, Altuve is batting .349 with a .439 on-base percentage. He leads the team with 36 extra-base hits.

"He's held up really well," Mills said. "If there was any time that he kind of struggled, it was probably going into the All-Star break. I think a lot of that was the anxiety of rumors and people talking about him being an All-Star."

Pearce, Greene have provided boost for Astros

HOUSTON -- The additions of infielders Steve Pearce and Tyler Greene have helped to legitimize the Astros' batting order, and it's finally paid dividends in terms of wins and losses. The Astros had won back-to-back games heading into Sunday.

Greene made only his second start on Sunday after being acquired in a trade with the Cardinals, but he went 2-for-5 with a double and a homer in his first start on Saturday, and scored a run as a pinch-runner on Friday.

"It's a great start, especially with a new team and new guys, and you want to fit in and feel like you can gain some trust that you can contribute to a win and move forward," Greene said. "[Saturday] was a great day for the team and a great day for myself."

Pearce, claimed off waivers two weeks ago, was hitting .382 with a .465 on-base percentage in his first 11 games with the Astros, including nine starts. He went 3-for-4 on Saturday to extend his career-best hitting streak to seven games.

"Their ability to run and take the extra base and their experience is great," Astros manager Brad Mills said.

Astros activate Castro from 15-day DL

HOUSTON -- The Astros activated catcher Jason Castro from the 15-day disabled list following Sunday's 5-3 loss against the Brewers and optioned catcher Carlos Corporan to Triple-A Oklahoma City. Castro will join the club on Monday in Chicago for the series opener against the Cubs.

Castro has been out since July 8 with right knee effusion, which is discomfort in his surgically repaired knee. He hit .301 with two homers and 12 RBIs in his last 83 at-bats before going on the DL, and hit .462 (6-for-13) during his Minor League rehab at Oklahoma City.

"He's swung the bat so well on his rehab, we're getting him back at a good time -- it appears, anyway," Astros manager Brad Mills said. "There's no doubt a guy with his tools and his ability, to get him back is going to be nice."

Castro missed all of last year after undergoing ACL surgery and had been catching about two out of every three games prior to his knee acting up, splitting time with Chris Snyder. Corporan hit .304 with a .353 on-base percentage in his last 16 games.

"There's no doubt he really helps us out offensively," Mills said. "He's swung the bat really well during the whole rehab experience."

Elias gets right to work in new position with Astros

HOUSTON -- Mike Elias has hit the ground running. Elias, named by the Astros as their new director of scouting on Saturday, was at Petco Park in San Diego on Sunday to watch some of the top high school players compete in the Perfect Game All-American Classic.

Elias, 29, will oversee amateur scouting and the First-Year Player Draft. He joined the Astros in January as a special assistant to the general manager/scouting. Prior to joining Houston, Elias had been in the Cardinals organization since 2007, where he served as a scout before being promoted to manager of amateur scouting.

"It's an exciting time, and it's certainly an exciting challenge going forward, sort of continuing the progress we've got going," Elias said. "There's a lot of positive signs, and we're sort of hoping to add to that and continue to make progress via the Draft. It's been a busy couple of days here and it's been hectic. You hear from a lot of friends and people throughout the industry. It's a big challenge, but I'm ready."

The Astros had the No. 1 overall pick in this year's Draft, and will likely have it again in 2013. Elias understands the importance of being able to take advantage of every Draft, especially when you're rebuilding.

"When you pick as high as we did [this] year and it looks like we'll be doing it again next year, the stakes are even higher," he said. "Fortunately, we've been preparing for this. Our scouts and our department have done a great job preparing for next year's Draft. We spent the whole summer scouring college summer leagues, high school showcases and basically getting our ducks in a row for the next spring time when the gun goes off and you have four or five months to line up the Draft board."

Elias said next year's Draft will have pockets of talent, with lots of good high school pitching, especially left-handers, and some good college arms and catching depth.

"It's probably comparable in talent overall as [this] year's Draft," Elias said.