Jake Westbrook gave up one run over seven innings and St. Louis exploded for eight runs in the third inning in a 13-1 win over the Milwaukee Brewers on Friday night.
St. Louis, which set a season high both for runs in an inning and in a game, won for the eighth time in its last 12.
Milwaukee has lost three of five.
Westbrook (3-1) gave up seven hits, struck out five and did not walk a batter. He has allowed two earned runs or less in all four of his starts this season.
Jon Jay had three hits and drove in three runs to pace a 15-hit attack. Skip Schumaker added two hits and three RBIs, and Matt Holliday had three hits and knocked in a pair.
Jay and Matt Carpenter drove in two runs each in the third as the Cardinals sent 12 batters to the plate. They chased Milwaukee starter Yovani Gallardo, who gave up eight earned runs in two innings.
Gallardo (1-2) lost for the ninth time in 10 regular-season starts against St. Louis. He has a 7.05 ERA in 13 starts against the Cardinals and has given up eight earned runs twice.
Carlos Beltran and David Freese drove in Jay and Holliday to start the eight-run outburst. Yadier Molina drew a walk and Carpenter ripped a 3-2 pitch off the center-field wall to push the lead to 6-1. Schumaker followed with a run-scoring hit and Jay added a two-run single. Holliday capped off the frame with a run-scoring single to right.
St. Louis last scored eight runs in the fifth inning of a 13-5 win over Chicago on July 30, 2011.
The Cardinals have scored nine runs or more five times this season.
Milwaukee jumped to a 1-0 lead on successive singles by Nyjer Morgan, Ryan Braun and Aramis Ramirez in the first. Westbrook allowed just four hits the rest of the way.
St. Louis starting pitchers have recorded 12 wins the season, the highest total in both leagues.
The Cardinals have outscored their opponents by an NL-leading 49 runs this season.
NOTES: Milwaukee had given up the first run in its previous eight games before scoring in the top of the first Friday. ... Molina will be presented with his fourth consecutive Gold Glove award prior to Saturday's game. ... Kyle Lohse (3-0, 0.99 ERA) will face Milwaukee's Marco Estrada (0-0, 2.45) in the second game of the three-game set on Saturday. ... The Cardinals, who began a six-game homestand Friday, played 13 of their first 19 games on the road.