The New York Yankees beat the Oakland Athletics 2-1 on Friday, leaving the Baltimore Orioles one game behind the American League East leaders.
The Yankees' Russell Martin homered in the 10th inning against Sean Doolittle after Brandon Moss hit a towering drive to right off Rafael Soriano with one out in the ninth to spoil a dominant three-hit outing by CC Sabathia.
Defeat dropped the A's one game behind the Orioles in the battle for the top wild-card spot after making it four defeats out of five.
Martin's second game-ending homer this season gave the Yankees their ninth win in 11 games.
The Orioles beat the Boston Red Sox 4-2 with Matt Wieters driving in three runs and Miguel Gonzalez pitching 6 and 1/3 solid innings.
Jon Lester lost for the first time in his 21 career starts against Baltimore. Gonzalez allowed two runs and seven hits as the Orioles improved to 6-1 this season at Fenway Park.
The Tampa Bay Rays thumped the Toronto Blue Jays 12-1 to remain in play-off contention.
James Shields pitched seven shutout innings and Ben Zobrist and Jose Molina both homered.
The Kansas City Royals were 6-3 winners against the Cleveland Indians as Luis Mendoza pitched into the seventh inning in his first start since illness.
The Los Angeles Angels defeated the Chicago White Sox 6-2 and Seattle were 6-3 winners over Texas.
Resurgent Philadelphia inched closer to a National League play-off place with a 6-2 victory over the Atlanta Braves.
Kevin Frandsen, Ryan Howard, Carlos Ruiz and Chase Utley all hit solo homers as the Phillies moved to within three games of St Louis for the league's second wild-card spot with a fourth straight win.
Milwaukee and Los Angeles also stand in Philadelphia's way with 11 games remaining and the Braves are also in the play-off picture despite the loss to Philadelphia.
Kyle Kendrick allowed two runs and five hits in 6 and 2/3 innings, striking out six.
The Brewers enhanced their play-off chances with a 4-2 defeat of the Washington Nationals.
Ryan Braun and Aramis Ramirez had consecutive RBI hits in the ninth inning off Nationals closer Tyler Clippard as the Brewers extended their season-high winning streak to six games with this victory.
With the Cardinals losing the Brewers moved to within 1 1-2 games of St Louis for the final wild-card spot.
The Chicago Cubs went to 11 innings before edging out St Louis 5-4, Darwin Barney spoiling Chris Carpenter's season debut with a two-run, game-tying homer with two outs in the ninth.
David DeJesus hit a game-ending single in the 11th to secure the win for the Cubs.
The New York Mets avoided falling into last spot in NL East with a 7-3 defeat of the Marlins to leave the Miami side propping up the rest.
Scott Harrison hit a two-run homer and an RBI triple and Ike Davis hit a solo homer as the Mets avoided making it 10 straight losses at home.
The Cincinnati Reds saw their first chance to clinch the NL Central title slip away as they lost 3-1 to the Los Angeles Dodgers in a game which went to 10 innings.
Arizona thrashed Colorado 15-5, Houston were 7-1 winners over Pittsburgh and San Francisco saw off San Diego 5-1.
