BOSTON -- Jon Lester struck out a career-high 15 batters and allowed only one hit over eight dazzling innings, and left fielder Jonny Gomes had a grand slam as the Boston Red Sox rolled to a 6-3 victory over the Oakland Athletics on Saturday.
Designated hitter David Ortiz and catcher David Ross also hit home runs for the Red Sox, who won their second straight after dropping both ends of a doubleheader to Tampa Bay on Thursday.
However, this one belonged to Lester.
The left-hander carved up the first-place Athletics, striking out nine of the first 12 batters and retiring 20 of the first 22, allowing only a bloop single to shallow right field by left fielder Craig Gentry leading off the third.
After opening the eighth with his second walk of the game, Lester struck out the next three batters, setting a career high by fanning Gentry, who had been the only Oakland player not to go down on strikes.
His afternoon came to an end when he got right fielder Josh Reddick looking at his 119th pitch.
Boston's bullpen nearly ruined Lester's masterpiece.
Chris Capuano faced four batters in the ninth, failing to record an out while giving up an RBI double to shortstop Jed Lowrie that led to a second run on a throwing error by Gomes.
Closer Koji Uehara walked designated hitter Yoenis Cespedes to load the bases and catcher Derek Norris hit into what should have been a double play, but after recording the out at home on a toss from Uehara, Ross threw wildly to first, allowing a run to score.
With runners on second and third, Uehara struck out first baseman Alberto Callaspo and got pinch-hitter Brandon Moss to fly out to end the game.
Gomes provided Lester all the support he would need in the first inning.
Oakland starter Tommy Milone (0-3) loaded the bases on a single to shortstop Xander Bogaerts and walks to second baseman Dustin Pedroia and Ortiz before Gomes deposited his first pitch into the seats above the Green Monster.
It was Gomes' fifth career grand slam and the second in as many days for the Red Sox, after Pedroia belted one in Boston's 7-1 win on Friday night.
Ortiz's sixth home run of the season in the third made it 5-0 and Ross added a solo shot in the fourth.
Milone gave up six runs and six hits over four-plus innings, striking out five and walking four.
NOTES: DH David Ortiz's home run was the 437th of his career and 379th as a member of the Red Sox, tying Dwight Evans for fourth on the club's all-time list. ... Oakland 3B Josh Donaldson failed to reach base for the first time in his last 25 games. ... LHP John Lester's previous career best was 13 strikeouts on July 24, 2010, in a 5-1 loss to Seattle. ... The Red Sox have hit three grand slams this season. ... LF Jonny Gomes' last grand slam came against Minnesota on May 8, 2013. ... Oakland RHP Sonny Gray (4-1, 1.76) will oppose Boston RHP John Lackey (4-2, 3.83) in the finale of the three-game series Sunday.