This is the first meeting between Boston and Oakland this season. Last year, the Red Sox took six out of 10 from the A's.
Boston heads into the second half with a three-game lead on the Yankees in the American League East.
"I think we have a great ballclub put together here," said Red Sox closer Jonathan Papelbon. "There's no doubt about it. The way the entire club is put together from top to bottom, from A to Z, I think we have a great club and can definitely make a World Series run."
In order to do that, the Red Sox will need continued brilliance from Papelbon, who has a 0.59 ERA after allowing just three runs in his first 40 appearances.
BOS: RHP Jon Lester (4-0, 3.06)
Lester continues to hold his own. He finished off the first half by notching a victory over the defending World Series champion White Sox. The Red Sox have won Lester's last five starts and opponents are hitting just .256 off him. This is his first career appearance against Oakland.
OAK: RHP Esteban Loaiza (3-5, 6.43 ERA)
In his last start, Loaiza yielded four runs over 5 1/3 innings against the Angels. He tied a career high by giving up four homers. Luckily they were all solo shots and the A's ending up winning, 7-5. The 34-year-old is 3-2 with a 4.70 ERA against the Red Sox in eight career starts.
Player to watch
Nobody wants to have a better second half than Jason Varitek, who enters Thursday's game hitting .232.
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Friday: Red Sox (RHP Josh Beckett, 11-4, 4.75) vs. Oakland (RHP Dan Haren, 6-7, 3.52), 7:05 p.m. ET
Saturday: Red Sox (RHP Curt Schilling, 10-3, 3.60) vs. Oakland (LHP Barry Zito, 8-6, 3.29), 7:05 p.m. ET
Sunday: Red Sox (RHP Tim Wakefield, 7-8, 4.05) vs. Oakland (RHP Joe Blanton, 8-8, 4.95), 2:05 p.m. ET
Ian Browne is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.