HOUSTON -- Left-hander Gustavo Chacin joined the Astros on Tuesday for the second game of their series vs. the D-backs after having his contract purchased from Triple-A Round Rock.
Chacin, who is 1-1 with a 3.65 ERA in five starts at Round Rock, replaced the disabled Tim Byrdak as the lefty in the bullpen, but manager Brad Mills said he won't be limited to that role.
"Because of what he's done and having been used as a starter and been stretched out, we're able to use him against lefties, and if we can stretch him out, we can do that, as well," Mills said.
Chacin, who had not made a relief appearance in his big league career entering Tuesday's game, is 25-15 with a 4.18 ERA in 58 career starts, all coming with Toronto from 2004-07. He won 13 games in 34 starts for the Blue Jays in 2005.
"I need to get used to doing that type of job," Chacin said. "Things are pretty much the same, because you've got to throw strikes no matter what. That's what I'm going to try to do. I've got to get a feel in that role and get used to it and throw strikes and get lefties out. That's what I'm going to try to do."
Quintero catches Oswalt for first time
HOUSTON -- For the first time in his career, Humberto Quintero got the chance to catch Roy Oswalt in a regular-season game when he started at catcher Tuesday. J.R. Towles caught Oswalt's first five starts of the season, but the battery appeared to have a little trouble communicating last time.
Astros manager Brad Mills said if there were any communication problems, he wasn't aware of them.
"It wasn't communicated to me by Roy or anyone else," Mills said. "I really don't have an answer for that question. We really wanted to change things up a little bit because of the way we've done it so far and go from there."
Quintero has caught Oswalt in Spring Training but was surprised when bench coach Al Pedrique called him Monday night and told him he'd catch Oswalt. The two haven't been paired up despite being teammates for five seasons.
"I feel happy because I never caught him before in five years, and I hope everything is going to be good between him and me," Quintero said.
The other players to catch Oswalt are: Brad Ausmus (200 games), Raul Chavez (45), Ivan Rodriguez (24), Chris Coste (six), Tony Eusebio (five) and Eric Munson and Gregg Zaun with two games each.
Byrdak not taking chances with hamstring
HOUSTON -- After dealing with a strained right hamstring since Spring Training, reliever Tim Byrdak decided following Monday's game to not push the injury and go on the 15-day disabled list for the first time in nearly three years.
Byrdak, 36, had appeared in 13 games and was 1-0 with a 5.23 ERA, but he said during the past three or four outings that he didn't feel he was getting through the extension side of home plate during his delivery. As a result, his breaking ball has been about 78-79 mph, which is down from the 81-84 mph he threw last year routinely.
"I'd rather go ahead and get some time now, and since we're early in the season, get it right and finish strong for the rest of the year instead of possibly going out there and blowing the shoulder or elbow out," Byrdak said. "I'm too late in my career -- if I have an injury like that, my career is over."
Byrdak was the only Astros relief pitcher to stay healthy for all of last season, appearing in a club-high 76 games.
"That's one of the frustrating things about it is that it bothers me enough to be effective out there, but it's still not quite enough where I can't pitch," Byrdak said. "I can pitch, but I'm not the same person I am. I need to be the same person I was last year.
"I took a lot of pride in the fact that last year I was the only guy that didn't go on the DL the whole course of the year and pitching almost 80 games, and I wanted to build on that. This is something that came up, and we felt the need to take care of it now."
Astros release former first-round pick
HOUSTON -- Max Sapp, the Astros' top pick in the 2006 First-Year Player Draft, has been released by the club, general manager Ed Wade confirmed Tuesday.
Sapp, a catcher selected No. 23 overall out of Bishop Moore High School near Orlando, Fla., hadn't played since nearly losing his life in a battle with meningitis following the 2008 season. He played two-plus seasons in the Astros' organization -- never above Class A -- and was a career .224 hitter with seven homers and 81 RBIs in 210 games.
"It became apparent that he would physically be unable to perform," Wade said.
Sapp, who received a $1.4 million signing bonus, hit .200 with four homers and 29 RBIs in 74 games in 2008 for Class A Lancaster and spent much of the offseason in the hospital battling viral meningitis. He missed all of last season while trying to recover.
Houston drafted Sapp, a left-handed hitter, after he batted .572 with nine homers and 48 RBIs during his senior year in high school in 2006.
Berkman not worried about fans on field
HOUSTON -- Lance Berkman was a rookie, sitting in the County Stadium dugout in Milwaukee in 1999, when a fan ran onto the field and jumped on the back of teammate Bill Spiers, who suffered a black eye and bloody nose.
A day after a fan in Philadelphia was subdued with a Taser gun after he ran onto the field during a Phillies game, Berkman said he's never felt threatened by fans coming onto the field.
"I've always been entertained when somebody runs out there," Berkman said. "It's always fun watching the security people try to catch them. The best I ever saw was Montreal. The guy eluded capture for five minutes, which is a long time. They couldn't catch him. It's part of the deal. It's not something we think about."
Berkman vividly remembers the Spiers incident.
"It was crazy," Berkman said. "I actually thought someone in our bullpen had gotten into a fight with their bullpen, and we couldn't figure out what the commotion was. When we got out there, obviously there was a fan involved, and it was kind of a crazy situation."
As far as the use of a Taser, Berkman said fans should be ready for the worst if they come onto the field.
"I think if a guy jumps onto the field and get Tasered, he deserved it," Berkman said. "I'm not into causing anybody permanent damage, but I don't think Tasering does that. It's just a shock to the system."
Brian McTaggart is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.