PHILADELPHIA -- It wasn't a government secret, but the Astros treated the identity of Tuesday's starting pitcher as such for a variety of reasons.

"What's today, Tuesday?" Jordan Lyles said. "Then I found out on Sunday and flew in yesterday. I stayed at the hotel because no one was sure what the weather was going to do."

With storms throughout the night and morning, the Astros wanted to wait to make a roster move in case one wasn't necessary. Just before noon ET, Astros manager Brad Mills received a telephone call from Phillies general manager Ruben Amaro Jr., who informed Mills the game would start on time.

Less than 20 minutes later, the Astros confirmed that Lyles would be called up from Triple-A Oklahoma City to make the start. David Carpenter, who gave up a home run to Phillies third baseman Placido Polanco on Monday night for Polanco's 2,000th career hit, was sent to Oklahoma City.

"[Carpenter] has Major League stuff," Mills said. "He's a Major League pitcher; we just want him to make some Major League pitches."

Lyles, meanwhile, did all the Astros asked of him and can now prepare for a second start, according to Mills.

"For the most part it went pretty well," said Lyles, who allowed three runs, two earned, in six innings of work. "I left a couple of pitches up. I wish I had the [home run ball to Brian Schneider]. I just left that up, and the [home run Hunter Pence hit] was a cutter that slid back into the zone."

To rest Lowrie, Astros give nod to Gonzalez

PHILADELPHIA -- The decision to start rookie Marwin Gonzalez on Tuesday afternoon against Phillies left-hander Cliff Lee was made several days before the Astros arrived in Philadelphia.

It had nothing to do with the weather, which played havoc on Houston's decision on a starting pitcher. Nor did it have to do with the fact that Gonzalez pinch-hit his first Major League home run off Phillies starter Joe Blanton in Monday night's 5-1 loss.

It had everything to do with usual starting shortstop Jed Lowrie, who manager Brad Mills said needs to get a day off every now and again. Lowrie, who played a career-high 88 games with Boston in 2011, is coming off shoulder and wrist injuries. Lowrie has played in 28 of the Astros' 35 games, and he has hit just .227 against lefties this year.

"You can look it up. I'm sure he's played in this many consecutive games before," Mills said. "But we want to be careful. I like that he wants to play every day. I like that he's a workhorse, but we also have to be smart."

Worth noting

While not common, Astros manager Brad Mills has had some experience with late roster moves, like the one the team made with starter Jordan Lyles.

"In 2001, we were playing the [Korean national team] in Taipei," Mills said, referring to his time as a bench coach for USA Baseball. "They warmed two people up, and since we were the home team, we had to hand our lineup in first at home plate. After we did, the guy who handed it in for them looked at it and picked the right card. One of the funniest things I've ever seen."