"I felt going out there and felt good going back out there after the rain delay," the 22-year-old right-hander said after a 2-0 victory over the San Francisco Giants on Saturday. "It's pretty crazy how much it rains, actually. I'm pretty used to it."
The experience was brand new for rookie Oscar Taveras, who made the Giants pay for a hanging curveball, then made a curtain call during his major league debut.
"What a great day for him, one I'm sure he'll never forget, and neither will we," manager Mike Matheny said. "For him to come up and do it in that situation, it's kind of mind-boggling."
Wacha worked six innings of three-hit ball in his fifth rain-delayed start of the season and Taveras homered in his second career at-bat.
"Everybody knows it's gone," Taveras said. "That was a good swing right there. I'm so happy right now."
Yusmeiro Petit (3-3) gave up two hits in six innings for the Giants, but one of them was Taveras' 418-foot drive in the fifth. Petit subbed for injured Matt Cain, placed on the 15-day disabled list with a hamstring injury, for the second straight start.
"Our guy did a good job," Giants manager Bruce Bochy said. "We just didn't do anything offensively."
The Cardinals have piled up 6 hours, 30 minutes of idle time in Wacha's starts, with delays of 51 and 47 minutes Saturday. The total includes a 61-minute weather delay before the first pitch against the Yankees his last start for a storm that failed to materialize, and the Cardinals lost in 12 innings.
Wacha's debut a year ago against the Royals was delayed more than 4 1/2 hours after the bullpen gave up the lead and finished at 3:14 a.m.
"This guy's going to be tough as nails, if he's not already," Matheny said of last fall's NLCS MVP. "You can't put a young pitcher through much more than what he's been put through."
Rain began to fall heavily during Taveras' at-bat with one out in the fifth while fans opened umbrellas or headed for cover. The game was halted for the first time after the 21-year-old outfielder, the team's prized prospect, hammered a 1-0 pitch over the right field wall.
"That kid's a stud," said Wacha, who's just one year older. "Everyone knows what he's capable of. That was a big-time homer for us."
Petit was impressed after seeing Taveras for the first time.
"He's got a good swing, you know," Petit said. "He pulls everything. I tried to stay away and I missed one."
Wacha (4-3) gave up one hit and dealt with just one base runner the first five innings, a double by Michael Morse leading off the second. He returned after a 47-minute delay to work a scoreless sixth, allowing two-out, two-strike hits to Hunter Pence and Pablo Sandoval before striking out Morse, the cleanup man, on three pitches -- the last a changeup.
The St. Louis bullpen retired the last nine in order. Sam Freeman and Pat Neshek worked a scoreless inning apiece, combining for three strikeouts, and Trevor Rosenthal struck out the side in the ninth for 16th save in 18 chances.
Matt Carpenter had a single and walk and is batting .367 (21 for 57) during a 13-game hitting streak, the longest current run in the National League. Matt Holliday walked in the eighth and has reached base in all 27 home games.
Giants C Buster Posey missed his third straight game with tightness in his lower back. Bochy said Posey could return Sunday or get another day with the team off Monday. ... Giants lefty Madison Bumgarner was 5-0 with a 2.08 ERA in May with 48 strikeouts in 39 innings. ... Tim Hudson (5-2, 1.92) opposes Lance Lynn (6-2, 3.13) in the series finale on Sunday. Lynn shut out the Yankees in his first career complete game his last start and Hudson has worked seven or more innings in all but two of his 10 starts. ... Peralta had been 5 for 46 with runners in scoring position before his RBI double. ... Neshek has thrown 20 1/3 consecutive scoreless innings his last 22 outings. ... Sandoval has hit in 11 straight.