Boston moved one game behind AL East leader Tampa Bay after preventing a three-game sweep. New York, which had been 8-0 since the All-Star break, remained three games back.
The Red Sox slumping hitters capitalized on a rare poor performance by a New York starter.
They scored in each of the first four innings, taking a 7-0 lead against Sidney Ponson (6-2), who hadn't lost since May 26. It was only the second time in 17 games that a Yankees starter allowed more than three earned runs.
Jon Lester (9-3) stayed unbeaten since his last loss on May 25 with his sixth win in nine starts despite working out of trouble in four of the first five innings.
But the Red Sox won with offense after losing 1-0 and 10-3 in the first two games of the series with a total of 12 hits. They had 15 on Sunday as Ramirez's concerns didn't bother him at the plate. He went 3-for-5 with a fly out deep to center field.
Before the game, he said "if the Red Sox think they can find a trade that's going to make their team better and both sides are going to be happvious side session. ... New York's Hideki Matsui, sidelined since June 22 with a left knee injury, is scheduled to hit both off a tee and soft toss pitches on Monday before the Yankees home game against Baltimore.
