Not even he can explain how.
In Monday's opener, Nady hit the tying homer with two outs in the ninth inning off closer Brad Lidge. The Pirates won 4-2 in 10 innings.
"It's just one of those things," said Nady, who has knocked in a run with each of his three hits in the series. "It's still early and I'm just trying to give quality at-bats."
Pirates starter Ian Snell struck out a career-high 11, but didn't get a decision. He gave up Carlos Lee's RBI single in the sixth that gave Houston a 2-1 lead.
But the Astros' bullpen failed again -- and this time, Lidge didn't even throw a pitch.
Ronny Paulino singled to left to score Wilson and tie the game. Nady followed with an RBI single to right.
"It wasn't like he really got beat up," Houston manager Phil Garner said about Wheeler. "But those things are going to happen once in a while."
The Pirates started 0-6 last season and were 3-79 when trailing after seven innings. They've already won two such games this year and matched their best start since 2003, when they opened 4-0.
"This was two very good games for us," manager Jim Tracy said. "A lot of things are happening good. We did some things again tonight that took us a while to figure out last year."
Houston starter Jason Jennings retired the first five Pirates he faced before Nady homered in his second consecutive at-bat in Houston, sending a 2-0 pitch onto the left-field porch.
Snell was almost untouchable through the first five innings, striking out 10 of the first 15 Astros he faced.
Only 25, Snell was already making his 39th career start, and the experience is starting to show.
"Last year, I probably would've had a little bit of jitters in a game like this," he said.
He looked unfazed all night in Houston, even when Adam Everett led off the third with a double down the left-field line. Snell regrouped, fanning Brad Ausmus, getting Jennings to fly out and striking out Biggio.
"Everything was working," Snell said, "and they were swinging at a lot of pitches and that helped me out."
Snell started the fifth with his ninth strikeout, fanning Morgan Ensberg, but Jason Lane homered into the left-field seats. Lane started in right field in place of Luke Scott, who homered in the opener but didn't start Tuesday because of a stiff right elbow.
Snell struck out Ausmus for the second time to end the fifth inning and match his previous career high for strikeouts (10).
"The job he did was a fairly dominant performance," Tracy said.
Orlando Palmiero, pinch-hitting for Jennings, led off the sixth with a single to right.
After Palmeiro reached, Snell returned to form, striking out Biggio for the third time. Chris Burke grounded out and Snell intentionally walked Lance Berkman to get to Lee, the slugger who signed the richest contract in Astros history in November.
Lee made up for two strikeouts with a bloop single to center that scored Palmeiro and gave Houston a 2-1 lead.
Tracy didn't see that as a glitch in Snell's performance.
"That was just a very good hitter hitting a very good pitch," Tracy said. "I've seen Snell pretty good and I'm seeing him that way again. He's a pitcher who's growing and he's starting to believe he belongs here."
But Wheeler couldn't hold the lead and accepted the blame that Lidge shouldered the previous night.
"I put myself in position to get out of that inning with one pitch and I just wasn't able to make that pitch," said Wheeler, who had a 2.52 ERA in 75 appearances last season.
- Pirates RHP Brad Lincoln underwent Tommy John surgery on his pitching elbow and will miss the 2007 season. Lincoln was the Pirates' first-round draft pick last season. The Pirates expect Lincoln to miss 10-12 months, but be ready for the 2008 season.
- Pirates RHP Dan Kolb and OF Luis Matos accepted their assignments to the minor leagues and are scheduled to report to Triple-A Indianapolis on Wednesday.
- Scott pinch-hit in the ninth inning, but grounded out to end the game.