That was more than enough runs to support pitcher Francisco Liriano (15-6) who got through eight scoreless innings, striking out six, to reach 15 wins for the first time. He has a 4-0 record against the Cardinals.
Oakland closed within two games of American League West leader Texas with a 4-3 win over Tampa Bay, and importantly overtook the Rays in the wild-card race.
Kurt Suzuki hit a three-run homer and Jed Lowrie hit a double in the eighth which drove in what proved the winning run.
Athletics starter Jarrod Parker extended his unbeaten streak to 17 straight starts, matching Catfish Hunter's Oakland record set in 1973.
Detroit padded its margin in the American League Central to 7-1/2 games over Cleveland by beating the Indians 7-2 in a rain-shortened game.
Victor Martinez doubled twice and drove in two runs for the Tigers, who won despite star slugger Miguel Cabrera being forced out of the game after just one at-bat due discomfort from an abdominal strain.
New York's Ichiro Suzuki hit a two-run homer and Robinson Cano singled in two runs during a five-run fifth inning which helped the Yankees beat Baltimore 8-5 in a clash of two teams on the fringe of playoff contention.
Despite the victory, there was ongoing concern for New York about the form of ace pitcher C.C. Sabathia (12-11), who lasted just 5 2-3 innings and yielded five runs.
The Orioles and the Yankees are 4 and 4-1/2 games respectively behind the second wild card pace.
Cincinnati's 9-6 loss at Colorado left the Reds 3-1/2 games off NL Central co-leaders Pittsburgh and St. Louis.
Todd Helton homered twice and matched a career high with six RBIs for the Rockies. It was his 28th multihomer game, and he is now just one hit off 2,500 in his career.
The first of his two three-run homers came in the fourth off Bronson Arroyo (13-10), roughed up for six runs over 3 1-3 innings in his shortest outing of the season.
Helton homered again in the seventh. Both times, Troy Tulowitzki and Wilin Rosario hit successive singles to set the table for Helton, who also had six RBIs against the Dodgers in 2003.
Los Angeles opened a yawning 10-1/2 game lead in the National League West by beating San Diego 9-2, with Yasiel Puig having four hits and two stolen bases for the Dodgers after getting benched in his previous game.
Adrian Gonzalez hit a pair of two-run homers for Los Angeles, which leads the division by as much as it has all season.
Boston capitalized on Tampa Bay's loss and extended its AL East lead to 3-1/2 games by edging the Chciago White Sox 4-3.
Red Sox starter Ryan Dempster (7-9) returned from his suspension for hitting New York Yankee Alex Rodriguez and pitched into the seventh inning, having held Chicago hitless through the first four frames.
Texas saw its AL West lead trimmed by a 3-2 home defeat at the hands of Minnesota.
Chris Herrmann hit a tying, two-run homer and Justin Morneau followed with a home run to lift the Twins to victory.
Minnesota snapped a five-game losing streak on a night when it looked as if the strikeout-prone Twins had no chance against the AL's strikeout leader Yu Darvish.
Instead, Darvish (12-6) had a third straight start without a win and his home run total jumped to 22 after having allowed only 14 last season.
Atlanta's Freddie Freeman hit a two-run homer in the first inning and that proved enough for the Braves to edge Miami 2-1.
Toronto's Mark Buehrle pitched seven scoreless innings to win his sixth straight decision and guide the Blue Jays to a 3-2 win which ended Kansas City's winning streak at five games.
New York's Ike Davis hit a two-run homer and Daniel Murphy scored from second base on a grounder as the Mets beat Washington 3-2.
San Francisco's Tim Lincecum pitched six spotless innings and third baseman Pablo Sandoval made a diving play in the field to preserve the Giants' 1-0 win against Arizona.
Los Angeles' Jered Weaver tossed six sharp innings to steer the Angels to a 5-0 win over Milwaukee.
Philadelphia's Michael Young had four hits, including a tiebreaking single in the ninth inning, as the Phillies rallied past Chicago for a 5-3 win, giving a victory to manager Ryne Sandberg in his return to Wrigley Field, where he was a long-serving star with the Cubs.
Seattle's Taijuan Walker did not allow an earned run over five innings in his major league debut, helping the Mariners defeat Houston 7-1.
