BOSTON (AP) -- A rejuvenated outlook and a weaker opponent were the perfect weekend mix for the Boston Red Sox.
Jed Lowrie's two-run triple highlighted a three-run fourth inning that helped Daisuke Matsuzaka to his 12th win and the Red Sox completed a three-game sweep with a 5-2 win over the struggling Oakland Athletics on Sunday.
Since the Red Sox completed a three-team, last-minute trade deadline deal that sent disgruntled outfielder Manny Ramirez to the Los Angeles Dodgers and brought Jason Bay from Pittsburgh on Thursday, the club has talked about a fresh approach in the clubhouse, emphasizing a relaxed attitude.
"We wanted to set a tone coming into the new month and I think we did that," Lowrie said. "The team's been revived. I don't think it was a matter of anyone coming or anyone going."
Bay continued his strong start with the Red Sox, going 2-for-4 with a pair of singles and two runs scored. He also threw out a runner trying to stretch a single.
"He's done a great job, playing great defense and getting on base," Boston first baseman Kevin Youkilis said. "That's why they brought him here. They thought he could come out and help this team win, and that's what he's doing."
Coincidence or not, departure has coincided with some wins.
"One of the things we talked about was not looking back or looking forward, just attacking what's at hand," Red Sox manager Terry Francona said of a team meeting held Friday. "We did that very well."
Boston improved to 40-16 at Fenway Park after losing five of the initial six games in a nine-game homestand. The Red Sox, just 24-32 away from home, play their next seven games on the road, beginning Monday night in Kansas City.
"I think where we're at right now, we can be pretty darn good," Red Sox catcher Jason Varitek said.
Daric Barton hit a two-run homer for the Athletics, who lost their sixth straight and 15th in 17 games.
"You look, bad series, going 0-3," A's manager Bob Geren said. "But we did get a few home runs here, which we've been lacking."
Oakland's five runs in the series came on three homers.
Matsuzaka (12-2), allowed two runs, four hits, walked two and struck out eight in six innings.
Jonathan Papelbon, the third reliever, worked a perfect ninth for his 31st save. Boston's bullpen held the A's to one single over the final three innings.
The Red Sox grabbed a 1-0 lead five pitches into the game when Dustin Pedroia doubled off the Green Monster and scored on Youkilis' single.
Boston increased it to 4-0 and chased starter Dallas Braden (2-2) in the fourth. Lowrie, the final batter Braden faced, hit a line drive over center fielder Carlos Gonzalez after Mike Lowell doubled and Bay singled. Gonzalez, playing shallow, had the ball go over his head as he broke back. Coco Crisp added a sacrifice fly.
"I don't think they'll pay shallow anymore," Lowrie joked.
Barton's homer cut it to 4-2 in the fifth.
Crisp's sacrifice fly made it 5-2 in the sixth.
"He threw a 100 pitches in the first [few] innings," Barton said. "We had a lot of guys on base, but just didn't capitalize on it."
There was a lighter moment in the fifth when lumbering DH David Ortiz walked and took off for second on the next pitch, not drawing a throw on his first stolen base of the season that amused the crowd as catcher Rob Bowen bobbled the ball.
Boston RF J.D. Drew was given the day off. ... Red Sox RHP David Aardsma, on the 15-day DL since July 20 with a strained right groin, pitched a perfect inning with two strikeouts in a rehab assignment with Triple-A Pawtucket on Sunday afternoon. ... The A's optioned Saturday's losing pitcher Dana Eveland to Triple-A Sacramento before the game and recalled LHP Dan Meyer, who pitched a perfect eighth. ... Geren said Crosby was a bit dizzy when he took him out in the eighth, and thought it may have been heat related. Crosby said he felt OK. ... A young boy seated along the third-base line was hit by Bay's foul liner in the fourth and quickly carried from the stands by a Red Sox security person. He was treated in a first-aid room in the park and later returned to his seat, team spokesperson John Blake said. ... Thunder rumbled around Fenway in the sixth, drawing 'oohs' from the crowd before play was halted by rain for 37 minutes. ... Ortiz had three stolen bases last season, his last Sept. 2. ... Youkilis has a 10-game hitting streak. ... Matsuzaka said he hoped to pitch the seventh before the rain came.