Boston, MA (Sports Network) - Mark Kotsay's RBI double in the eighth inning was the difference as the playoff-bound Boston Red Sox clipped Cleveland, 5-4, in the third contest of a four-game set at Fenway Park.

Kotsay finished 2-for-4 and drove in two for the Red Sox, who have won two in a row and three of four. David Ortiz, Jason Varitek and Chris Carter each knocked in a run.

After clinching their fifth playoff berth in six seasons on Tuesday, the Red Sox are chasing Tampa Bay for the AL East crown. The Red Sox are likely to get the wild card spot though, as the Rays reduced their magic number to one for winning the division, thanks to a 11-6 win at Baltimore Wednesday night.

David Aardsma (4-2) got the win, after hurling 1 2/3 innings of one-hit relief. Starter Paul Byrd was tagged for 11 hits and four runs over five frames. Manny Delcarmen notched his second save with a scoreless final inning.

Shin-Soo Choo, Jhonny Peralta and Victor Martinez each collected a pair of hits and an RBI for the Indians, who have dropped two in a row after a seven- game win streak. Josh Barfield also drove in a run.

Rafael Perez (4-4) took the loss, while Tribe starter Fausto Carmona was assaulted for five hits and four runs in just one inning.

Facing Perez, Jeff Bailey slammed a one-out pinch-hit triple off the Green Monster and Kotsay drilled a double down the line in right for a the go-ahead run. Though Varitek was walked intentionally, both pinch-hitter Jed Lowrie and Alex Cora grounded into fielder's choices to end the rally.

"That was a nice swing," Red Sox manager Terry Francona admitted. "It gave us a little spark and then (Kotsay) took a real nice swing off a guy that's real tough on lefties. We played a few different guys and we still found a way to win the ballgame."

Delcarmen entered in the ninth, and promptly walked Grady Sizemore. Jamey Carroll sacrificed him to second, but both Choo and Peralta fanned looking to end the contest.

The Red Sox jumped out to a 4-0 first-inning lead, chasing Carmona in the process. Back-to-back one-out doubles by Dustin Pedroia and Ortiz put the first Boston run on the board. Kevin Youkilis walked, and after J.D. Drew grounded into a fielder's choice, three straight singles -- by Kotsay, Varitek and Carter -- each pushed across another run.

Cleveland responded with a run in the second on Barfield's RBI single, then tacked on two more in the third. Carroll led off with a double and went to third on Drew's fielding error. Choo's infield single, helped along by Kotsay's throwing gaffe, plated Carroll and put Choo at second. He came home when Peralta dumped a single to left.

The Tribe knotted the game in the fifth. Choo and Peralta singled to start the frame. Martinez then singled in Choo before a double-play ball from Travis Hafner and a Ben Francisco groundout ended the inning.

"We had our chances, just like last night, we had our chances," lamented Indians manager Eric Wedge. "We let Byrd off the hook a few times. We did a good job of coming back and tying the ballgame and giving ourselves a chance, but ultimately, we were not able to push over the top."