Updated

The Boston Red Sox and the Oakland Athletics will square off in the rubber match of their three-game weekend series on Sunday afternoon at Oakland Coliseum.

The Red Sox had been winners of four straight heading into Saturday night's contest before losing in shutout fashion, 3-0.

A.J. Griffin (8-6) was outstanding in the triumph, pitching eight shutout innings while allowing just six hits and one walk with three strikeouts.

Grant Balfour pitched a scoreless ninth for his 42nd consecutive converted save opportunity dating back to last season.

Derek Norris got the scoring started with a solo home run in the fifth inning, his fifth of the season. Yoenis Cespedes and Coco Crisp added RBI singles for the home team.

For Boston, Jon Lester (8-6) was solid despite the setback, surrendering three earned runs over 6 1/3 innings of work.

Shane Victorino and Mike Napoli both recorded two hits on the night, with Victorino adding his 11th stolen base as well.

On Sunday, Boston will turn to Brandon Workman for the spot start. In his only previous outing of the season, Workman allowed three earned runs in two innings of work on July 10 versus the Mariners in his Major League debut.

The 23-year-old has moved quickly through the Red Sox farm system this season. After going 5-1 with a 3.43 ERA at Double-A Portland, he went 3-1 with a 2.80 ERA in six appearances with Triple-A Pawtucket before getting the call to the big club.

Oakland will counter with Bartolo Colon, who has been sensational this season at 12-3 with a 2.69 ERA. He was named to the AL All-Star Team for the third time in his sprawling career, also accomplishing the feat in 1998 with the Indians and 2005 with the Angels.

Colon had been the winner of eight consecutive starts prior to earning a hard- luck loss to the Cubs on July 3 (7 IP, 2 ER). He wasted no time getting back to his winning ways, however, allowing just one earned run over seven innings of work in a 2-1 victory against Pittsburgh on July 8.

"I've never pitched better than this year," the 40-year-old right-hander said following his latest outing. "This has been my best season."

Colon has gone 5-1 in nine starts at Oakland Coliseum this year with a 2.47 ERA.

Boston is now 3-2 versus Oakland this season.