Padres 11, Cardinals 3: Cameron Maybin belted a two-run homer among his three hits and surging San Diego romped in the series opener against visiting St. Louis.

Chris Denorfia had four hits and two RBIs and Will Venable drove in three runs as the Padres improved to 15-5 in their last 20 games and handed the Cardinals their fourth loss in five games.

Eric Stults (6-2) earned his fifth consecutive victory, giving up three runs on five hits in 5 1/3 innings, and San Diego won for the 19th time in 25 games at Petco Park.

Left-hander Jaime Garcia (4-7) lasted only three innings and allowed four runs on seven hits as St. Louis saw its lead for the second wild-card slot whittled to one game over the Los Angeles Dodgers.

Logan Forsythe and Everth Cabrera added three hits apiece as the Padres collected 17 against five Cardinals pitchers.

Pete Kozma went 3-for-4, including a two-run triple in the second inning for St. Louis, but San Diego answered with two runs in each of its next three at-bats - with all of the runs coming with two outs.

Maybin's two-run blast in the third put the Padres ahead to stay and Jesus Guzman and Yonder Alonso had RBI singles in the fourth for a 6-2 lead.

GAME NOTEBOOK: Cardinals 1B Lance Berkman will undergo season-ending knee surgery Tuesday. Berkman, who underwent knee surgery May 25, has made only one start since Aug. 3 because of recurring soreness in the joint. ... Padres LF Carlos Quentin left the game in the fourth with soreness in his right knee. He underwent surgery on the knee in March. ... Cardinals 3B David Freese returned to the lineup after sitting out Sunday's game with a mild ankle sprain. ... Forsythe was a home run shy of the first cycle in franchise history. ... Cardinals RHP Jake Westbrook will miss Thursday's scheduled start with a right oblique injury. Lance Lynn will start in his place.