HOUSTON -- Ryan Howard chose not to dwell on the would-be home run he lost on a blown call. Instead he went out on Sunday and hit one that couldn't be disputed.
Jimmy Rollins also homered as Philadelphia prevented the New York Mets from clinching the NL East. The second-place Phillies, however, are aiming at the wild card and are one game behind Los Angeles for that spot.
Howard's solo homer went to left field in the third inning. A day earlier, Howard hit a drive to left that was ruled a double by umpire Larry Poncino; replays appeared to show a young fan in the front row dropping the ball, and Poncino said after the game that he got the call wrong.
"I wasn't worried today. You can sit there and worry about it or just go out and play," Howard said. "But I'm glad it went out."
Howard tied a team record with 29 road home runs in a season. He's homered in 16 of the 19 parks he's played this year.
Wolf (4-0) won while pitching on three days' rest for the first time in his career. He won his career-best ninth straight decision, the first time a Phillies starter has done that since Steve Carlton in 1980-81.
Wolf said matching a mark of Carlton's was humbling.
"I shouldn't even be mentioned in the same sentence with Steve Carlton," Wolf said. "He was an incredible pitcher and he pitched so many, many years. I think he's got me on more than one level."
But Phillies manager Charlie Manuel was impressed with his effort.
"Wolfy did a very good job," Manuel said. "He got us right where we needed to be. He took us through those first innings."
The Phillies took all three games in Houston for their first sweep of the Astros since May 2002.
"We're in a lot better position than we were last year and I think everyone knows what it will take to make it," Howard said of the team's playoff hopes. "Everyone in the locker room is confident. This win was huge, especially against a team like Houston because they've beaten us so many times."
Wolf (4-0) blanked the Astros until Craig Biggio homered to lead off the sixth. With the sellout crowd chanting "Bi-ggi-o," he was able to break his 0-for-30 slump.
Wolf gave up another homer, a two-run shot by Aubrey Huff later in the inning that cut the lead to 5-3, before being replaced.
Houston closed to 6-4 on Lance Berkman's home run in the eighth.
Lieberthal homered in the fourth and hit another in the eighth.
The trouble began early for Astros starter Wandy Rodriguez (9-10) when Jeff Conine hit a ground-rule RBI double in the first. Rollins extended Philadelphia's lead to 2-1 when he led off the third with his 21st home run.
Rodriguez allowed six hits and four runs in five innings for his fifth straight loss. He has also had four no-decisions in that span and hasn't won since July 2.
"I felt bad because I really wanted to come out and win this game," Rodriguez said through a translator. "We know we needed it."
The Astros have lost six of their last seven and are 6½ games back in the wild card standings.
"I don't know how to describe how we're playing," Astros manager Phil Garner said. "We're certainly not playing winning baseball when you drop three in a row in a series when you need to when them. But it's not like we're looking to go out and lose either."
- The last time the Phillies swept the Astros in Houston was in May 1995 at the Astrodome.
- Philadelphia is 19-7 in Sunday games this season.