American League East leaders the Boston Red Sox crushed the Yankees 11-1 in the Bronx with Mike Napoli hitting a grand slam to help even the series with New York.
Daniel Nava added a three-run homer in the eighth to conclude the rout.
Felix Doubront (4-2) allowed a run on six hits while striking out six to end a five-appearance winless streak.
The Yankees chose to walk David Ortiz in the third inning, loading the bases for Napoli. Phil Hughes left a fastball over the plate and Napoli smashed it for his fifth career grand slam and a 5-0 lead.
Nava's blast to right-center in the eighth put the game beyond the Yankees at 8-1 and Stephen Drew hit a solo homer in the ninth.
The loss was New York's sixth in the last seven games but they will have chance for revenge when they face the Red Sox again on Sunday.
In the National League, Atlanta outfielder B.J. Upton drove in the winning run with a single in the 10th inning as the Braves extended their East division lead over visitor's Washington with a 2-1 win.
Jordan Walden (2-1) worked a perfect 10th for the win as four Braves pitchers combined on a five-hitter.
Andrelton Simmons gave the Braves a 1-0 lead with an RBI groundout in the third and Ian Desmond's two-out RBI single in the fourth levelled it up.