Chamberlain allowed three singles and struck out nine in a career-high seven innings, Mariano Rivera shut down a threat in the eighth and the Yankees improved to 7-0 since the All-Star game. They inched closer to the second-place Red Sox in the AL East after Boston started the day a percentage point behind Tampa Bay.
The only run scored in the third inning when Jason Giambi took advantage of an infield shift and hit a tapper to the spot vacated by shortstop Jed Lowrie, who was playing to the right of second base. By the time Lowrie raced back to retrieve it, Bobby Abreu, who had singled and advanced to third on Alex Rodriguez's single, scored easily.
Giambi reached on the single off Josh Beckett (9-7).
Chamberlain (3-3) made his 10th start since moving out of the bullpen on June 3. He had held a team scoreless just once before, on June 25 when he allowed six hits in 6 2-3 innings of a 10-0 win at Pittsburgh.
On Friday, he walked one, didn't allow a runner past second base and retired his last 10 batters, five on strikeouts, as the Yankees moved a season-high 12 games above .500.
Kyle Farnsworth put runners at first and second with one out in the eighth on singles by Lowrie and Coco Crisp. Then Rivera came in, struck out Jacoby Ellsbury and retired Dustin Pedroia on a grounder to the mound. He allowed a one-out single to Kevin Youkilis in the ninth, then struck out the last two batters for his 26th save in 26 opportunities.
Earlier in the night, the Yankees acquired outfielder Xavier Nady and left-hander Damaso Marte from the Pittsburgh Pirates for top outfield prospect Jose Tabata and three minor leaguers, according to two people familiar with the deal who spoke on condition of anonymity because physicals were still pending.
The deal, which also sends right-handers Ross Ohlendorf and George Kontos and left-hander Phil Coke to the Pirates, is meant to bolster the Yankees' offense and bullpen ahead of next week's non-waiver trade deadline.
Chamberlain gave up singles to Pedroia in the first and Mike Lowell in the second. In the fourth, David Ortiz, returning after missing 45 games with an injured left wrist, singled when his grounder took a bad hop and eluded second baseman Robinson Cano. Lowell then walked with two outs, but J.D. Drew struck out.
