The 24-year-old Hirsh wasn't the only candidate to join the rotation. Right-hander Taylor Buchholz and lefty Wandy Rodriguez also received consideration.
But it's Hirsh that had the upper hand. The right-hander entered his start Tuesday with a sparkling 13-2 record and a 2.13 ERA over 22 games, allowing 32 earned runs over 135 1/3 innings. He walked 51 and struck out 116.
"He didn't impress me in Spring Training," manager Phil Garner said. "It proves that you can't do yourself any harm as long
as you work hard and put forth a good effort. I think his back bothered him in spring and he never was right. We didn't
really see the true pitcher that he's been now.
"It will be interesting to see how he throws. He's been pitching very, very well. He impressed everybody down there and
everybody in our system. We'll give him a shot up here."
Moving around: Chris Burke is scratching and clawing for any playing time he can get, so where he's playing is not as important as just simply seeing his name on the lineup card when he walks into the clubhouse.
Burke started in right field on Tuesday, a position he's played only a handful of times this season. He made two prior starts there, one in Colorado during which he dislocated his shoulder slamming into the wall, and one injury-free start in right on July 13.
Having played second, short, left, center and right, Burke is adjusting nicely to the everyman role.
"Right field is the flip side of left field," he reasoned. "And I've had plenty of exposure in left. I'm going to just try to turn my brain around and see if it works that way."
First base for now: First base is Lance Berkman's preferred position, but his reasons for playing there these days are health-related only.
Until the club is satisfied that Berkman's groin issues are 100 percent behind him, he'll continue to avoid right field, where he has started 30 games this year. Including Tuesday's game, Berkman has made 63 starts at first base.
"I feel pretty good," he said. "If I can start running like I was before I hurt my groin, there's no reason why I shouldn't be able to move back to the outfield."
Berkman estimated his groin is close to "90 percent, almost 100 percent" but said it's probably better to wait another three or four days, minimum, as a precaution. This is not a problem for him, considering he'd rather be at first base anyway.
"But it's hard to keep a versatile athlete such as myself in one spot," he joked.
Mix and match: Manager Phil Garner paired catcher Eric Munson with Brandon Backe on Tuesday, and if the combination works, he'll probably stick with that tandem for the time being.
The Astros began a stretch of 20 consecutive games without a day off on Tuesday, and Garner plans to give his backups ample playing time when the starters inevitably need rest.
Garner saw a good opportunity to give front-line catcher Brad Ausmus two full days off, including Monday's off-day. It's probably not the only day off Ausmus is going to receive.
"I'm going to need to give Brad some time along this stretch," Garner said. "Getting Munson with Backe, hopefully he'll get comfortable with him and we can use him a couple more times, and that way we don't have to fry the old man."
Deadline redux: More than a week has passed since the trade deadline, and Purpura acknowledged that the storylines that emerged from that rumor-filled day probably affected the team. He hopes the effects were more positive than negative.
"I had a number of players come up to me on Tuesday when we got to San Diego and said, 'I'm glad to be an Astro. I'm glad to be here. I'm glad I'm still here,'" Purpura said. "I think they were very sincere about it."
Purpura said he avoided the clubhouse for the week leading up to the trade deadline, sensing his presence may cause discomfort among players who wondered if they were on the trading block.
"I felt like guys were antsy around me," Purpura said. "I didn't want to create any more anxiety, but you don't realize how much anxiety is created just by the deadline."
Coming up: The Astros and Pirates reconvene on Wednesday for the second game of the three-game set, beginning at 7:05 p.m. CT. Right-hander Roy Oswalt (8-7, 3.34 ERA) will face Bucs righty Shawn Chacon (6-3, 6.62 ERA).