Jon Lester outpitched CC Sabathia, throwing eight strong innings Saturday to guide the Red Sox past the Yankees, 5-1.
Lester (14-8) allowed three hits and two walks with five strikeouts, extending his turnaround from a stretch of 11 starts between May 20 and July 13 when the lefty went 2-6 with a 6.27 ERA.
He is 6-2 in his last 11 starts and has trimmed his ERA from 4.58 to 3.75.
"I believe in myself, these guys believe in me and I knew going through what I went through in the middle of the year it was just a matter of time ... that things would take care of themselves," said Lester.
Sabathia (13-13) gave up nine hits, four walks and five runs with five strikeouts in six innings.
Shane Victorino and Jonny Gomes both had two hits and an RBI for the Red Sox, who have won the first two of the three-game series and nine of their last 11 overall.
The AL East leaders took the opener of the series 8-4 on Friday after Jarrod Saltalamacchia broke a tie game with a grand slam in the bottom of the seventh inning.
The Yankees, now 3-3 on a 10-game road trip and trying to stay in the AL wild card race, played without outfielder Alfonso Soriano, who was scratched from the lineup with a thumb injury he suffered earlier this week in Baltimore.
"It was bothering him yesterday but they said it was OK. Today it was worse. I'm not sure why," said Yankees manager Joe Girardi. "It's hard to figure out."
Soriano is day-to-day, Girardi said. X-rays were negative.
Lester retired the first four Yankees hitters on ground outs and was perfect over the first three innings.
Mike Napoli singled to lead off the second for Boston and later scored on a Will Middlebrooks ground out, and the Red Sox added two runs in the third inning on a double by David Ortiz and Gomes' single to make it 3-0.
Curtis Granderson's triple leading off the fourth was New York's first hit. He later scored on Robinson Cano's ground out, but Boston pushed its lead back to three runs in the bottom of the inning on Victorino's single.
Napoli walked, Gomes doubled and Daniel Nava made it 5-1 with a sacrifice fly in the fifth.
Lester threw 79 of his 115 pitches for strikes -- not a much better percentage than's Sabathia's 70-of-110. But after the Yankees scored in the fourth, the Red Sox lefty gave up just two more hits and a walk. Franklin Morales threw a 1-2-3 ninth for Boston.
Sabathia stayed on until he was replaced by Joba Chamberlain to start the seventh.
"They just seemed to string some hits together at the right time (against Sabathia)," said Girardi. "He did a good job of keeping the ball in the park but they got some two-out hits on him that hurt him."
Chamberlain gave up two straight walks but got a double play and a strikeout and no Red Sox runners reached base afterward. Matt Daley threw a perfect eighth for New York.
Lester's last start came against the Yankees, a 4-3 Red Sox loss last Sunday. He didn't get a decision ... The Red Sox and Yankees typically play some of the longest games in baseball. This one went just 2 hours and 43 minutes.