SAN DIEGO — The St. Louis Cardinals figured out San Diego right-hander Edinson Volquez the third time through the order.
Volquez allowed four runs on six hits in the fifth inning and the Cardinals went on to beat the Padres 10-2 Tuesday night.
Daniel Descalso hit his first career grand slam and had a career-high five RBIs, and Adam Wainwright won for the first time at Petco Park.
The game was tied at 1 going into the fifth.
"They definitely got more aggressive in that inning," Padres catcher John Baker said. "I think in the beginning, the first few innings, they wanted to wait and see what Volquez they were going to see. He was on his game and they didn't want to get into too many two-strike counts after that because he had all three pitches working. Any pitch that was up, even a little bit, they got a base hit on it."
Volquez (3-5) allowed five runs and eight hits in six innings, struck out five and walked one. He allowed four runs on six hits in the fifth.
"His first three innings, he pitched extremely well," manager Bud Black said. "First-pitch strikes, ahead in the count, good ball-strike ratio. They just strung some hits together in the fifth."
Descalso lined a 1-2 pitch from Anthony Bass into the Jack Daniel's Old No. 7 Deck in right-center with one out in the eighth, his second homer of the season. Jon Jay was intentionally walked ahead of him.
Descalso, hitting just .197 coming in, went 3 for 3 with a walk and scored three runs. He missed the cycle by a triple. He singled leading off the third and scored on Matt Carpenter's double. He hit an RBI double in the four-run fifth and scored on Carlos Beltran's two-run single.
Matt Holliday struck out opening the eighth but reached on Bass' wild pitch and Allen Craig singled. Padres first baseman Yonder Alonso tried for a reverse double play on Yadier Molina's grounder but his wide throw pulled shortstop Everth Cabrera off the bag and Craig was safe. Jay was intentionally walked and Descalso hit his slam.
Wainwright (6-3) held San Diego to one run and four hits in 7 1-3 innings, struck out six and walked one.
"He was pretty good to start," Baker said. "He's been a really good pitcher in the league for a long time. He's somebody who you have to keep the score close. If you give him a three- or four-run lead, he throws strikes, works fast and the defense plays well behind him."
The 6-foot-7 right-hander had been 0-2 with a 2.57 ERA in his previous three appearances at the spacious downtown ballpark, including two starts. That leaves New York's Citi Field as the only NL park where Wainwright has never earned a victory.
Padres rookie Jedd Gyorko had three hits.
NOTES: Padres lefty Clayton Richard made his second rehab start with Triple-A Tucson at Omaha, allowing two earned runs on five hits in six innings, with four strikeouts and no walks. ... Cardinals 3B David Freese was out of the lineup for the second straight game. He got three stitches in the base of his right thumb after getting spiked by Milwaukee's Norichika Aoki while tagging him out during a rundown Sunday. ... Padres LF Carlos Quentin sat out with a balky right knee. He had an awkward slide into home in Monday night's 4-2 victory. ... The series concludes Wednesday night when St. Louis LHP Tyler Lyons is scheduled to make his big league debut against rookie RHP Burch Smith (0-0, 15.63). Lyons will be the second Cardinals lefty in nine days (John Gast, May 4 vs. New York Mets) to make his big league debut in a start. Lyons was a ninth-round pick out of Oklahoma State in the 2010 draft.