The New York Yankees, the American League East leaders, ended their nine-game losing streak at Tropicana Field with a 4-3 victory over the Tampa Bay Rays on Wednesday.
Robinson Cano's two-run single off Jake McGee in a three-run eighth inning proved decisive in St Petersburg, dashing David Price's hopes of becoming the AL's first 12-game winner.
There was no such turnaround in fortunes for Boston, though, as the Oakland Athletics edged the Red Sox 3-2 to complete a three-game sweep, Jemile Weeks delivering the game-winning hit in the seventh.
Michael Brantley and Casey Kotchman each blasted three-run homers for Cleveland to help the Indians hammer the Los Angeles Angels 12-3 in their three-game series finale at Progressive Field.
Kevin Youkilis' walk-off single in the 10th inning lifted the Chicago White Sox to a 5-4 win over the Texas Rangers, the Detroit Tigers prevailed 5-1 against the Minnesota Twins, the Toronto Blue Jays overcame the Kansas City Royals 4-1 and the Baltimore Orioles saw off the Seattle Mariners 4-2.
In the National League, the East-leading Washington Nationals picked up their third straight win with a 9-4 triumph over the San Francisco Giants.
Ryan Zimmerman homered and drove in three runs as the Nats rallied from an early deficit to condemn the Giants to a second consecutive defeat.
The Philadelphia Phillies also enjoyed an emphatic win, snapping their six-game losing run in style with a 9-2 thrashing of the New York Mets.
Paul Maholm threw six solid innings in the Chicago Cubs' 5-1 victory against the Atlanta Braves, the left-hander giving up one run on eight hits.
The Los Angeles Dodgers returned to the NL West summit thanks to a 4-1 win over the Cincinnati Reds, the San Diego Padres beat the Arizona Diamondbacks 8-6, the Miami Marlins edged the Milwaukee Brewers 7-6 in 10 innings, the Pittsburgh Pirates toppled the Houston Astros 6-4 and the St Louis Cardinals were 4-1 winners against the Colorado Rockies.