(Reuters) - The New York Yankees took sole possession of top spot in the American League East with a win over Tampa Bay on Saturday, while Oakland's win over Baltimore moved the A's within striking distance of Texas in the AL West.
In the AL Central, the Chicago White Sox remain a game ahead of Detroit after both teams recorded victories on Saturday.
The Yankees (82-63) moved a game clear of Baltimore (81-64) after a 5-3 win over the Rays (78-67), Curtis Granderson hitting his 39th home run of the season to help New York to a 4-0 lead though five innings.
Tampa Bay's Evan Longoria homered in the sixth and the visitors scored twice more in the seventh to make it a one-run game, but the Yankees sealed the win when Alex Rodriguez drove in Robinson Cano in the eighth inning.
Yankees pitcher Ivan Nova made an impressive return from the disabled list to get the win.
"It's not that I didn't try to be focused in the past, but a game like today, especially coming back from the DL, you have to do everything you can to win this game," Nova told reporters.
"I came from my house mentally prepared to do that."
The Rays beat the Yankees on Friday but have lost four of their last five games to divisional rivals and slipped three games behind in the wildcard race.
The Orioles led 2-0 in Oakland after Mark Reynolds drove in a run in the second and Nate McLouth homered in the top of the third, but the A's put up five runs in the bottom of the third on the way to a 5-2 win.
Oakland (84-61) are now two games behind AL West leaders Texas (86-59), who lost 8-6 to Seattle.
The LA Angels suffered a 3-2 loss to Kansas City, dropping them 2 1/2 games back in the wildcard race.
The AL Central battle looks like it will go down to the wire after the White Sox (78-66) and Tigers (77-67) both won on Saturday, Chicago beating Minnesota 5-3 and Detroit beating Cleveland by the same scoreline.
Chicago led 4-0 into the seventh and pitcher Francisco Liriano was eyeing a no-hitter until Trevor Plouffe powered a two-run homer.
Atlanta took a 5-4 win over National League East rivals Washington after Nationals' relief pitcher Ryan Mattheus hit Andrelton Simmons with the bases loaded in the eighth inning.
The Nationals still lead the division by 6 1/2 games while the Braves maintained their stranglehold on the first NL wildcard spot.
The Dodgers tied the Cardinals for the second wildcard position after they rallied in the bottom of the ninth to beat St Louis 4-3 in Los Angeles.
Down to their last out, Dodgers pinch-hitter Juan Rivera hit a walk-off single after Luis Cruz drove in the tying run with a double.
However, it was not all good news for the Dodgers after they learned ace pitcher Clayton Kershaw had been scratched from Sunday's scheduled start due to inflammation in his right hip.
Kershaw has been ruled out indefinitely, perhaps for the remainder of the season, and his absence would be a major blow to a pitching staff already without Chad Billingsley and Ted Lilly.
Pittsburgh kept their hopes alive of reaching the postseason after they held off the Chicago Cubs to win 7-6 and move two games away from the second wildcard spot.
Milwaukee are a 1/2 game behind the Pirates after a 9-6 win over the New York Mets.
Philadelphia missed a golden opportunity to draw closer in the same wildcard battle, falling 5-0 to lowly Houston and dropping three games back.
(Reporting by Ben Everill in Los Angeles; editing by Peter Rutherford)
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