BALTIMORE -- There is no getting around it anymore. Daisuke Matsuzaka is in the worst slump of his rookie Major League season. The prized right-hander from Japan has been hit hard in four of his past five starts, culminating with what looked like a rock-bottom performance on Saturday night against the Orioles.

Matsuzaka and the Red Sox were pounded, 11-5, by a badly slumping Orioles team. Staked to a 4-1 lead after two innings, Matsuzaka had an inning of implosion for the second start in a row.

The Orioles tattooed him for seven in the third frame, capped by a two-out grand slam by Scott Moore. That was Matsuzaka's 72nd and final pitch of the night. Matsuzaka, who hadn't gone fewer than five innings in any previous start this season, was battered for six hits and eight runs over 2 2/3 innings. He walked three and struck out two.

"Yes, I would agree that right now is sort of a testing-time period for me where I need to be patient," Matsuzaka said through translator Masa Hoshino. "But, at the same time, I feel like I'm the one guy dragging on this team a little bit. For that, I feel very apologetic."

Overall, Matsuzaka slipped to 14-12, while his ERA rose to 4.44. In his past five starts, Matsuzaka is 1-4 with a 9.57 ERA.

"I don't think it matters," said Red Sox manager Terry Francona. "I don't get too caught up in that. What he did five games ago is basically meaningless, going forward or tonight. It has no bearing on where we're going."

Red Sox pitching coach John Farrell feels that Matsuzaka's biggest problem at the moment is that he is overthrowing -- and being too reliant on his fastball -- at the first sign of trouble.

"I think tonight kind of summarized things," Farrell said. "When he gets in a big inning, he's recently had a tendency to just rely on his fastball solely and trying to generate as much power as possible. As a result, I think he's sacrificing location. He's somewhat gone away from his offspeed pitches, and hitters have had a chance to go in and look hard and not really have to guard too much against anything soft in a pitch mix."

With the loss, the 86-57 Red Sox lead the Yankees by 5 1/2 games in the American League East. Their magic number for clinching the division remains at 15.

The Red Sox certainly started this game in strong fashion, getting a towering two-run homer by David Ortiz in the top of the first. Tike Redman got one right back for the Orioles by taking Matsuzaka over the wall in the bottom of the inning.

"Well, we started out good," Francona said. "We're scoring. [Matsuzaka] gives up a home run to Redman, fastball right over the middle."

No problem, said the Sox. They jumped right back on Orioles starter Jon Leicester in the second. J.D. Drew led off with a double. Julio Lugo and Jacoby Ellsbury slapped back-to-back, two-out RBI doubles to make it 4-1 in favor of Boston.

A comfortable start for the Red Sox turned into disaster in the bottom of the third, when Matsuzaka got shelled for seven runs. With the bases loaded and nobody out, Matsuzaka walked Nick Markakis to force in a run. Miguel Tejada roped an RBI single to left to get the Orioles within one. And Matsuzaka again issued a bases-loaded walk -- this time to Kevin Millar -- to tie the game at 4.

"I think it comes down to my inability to throw strikes, and being unable to throw strikes like that didn't give [Jason] Varitek a chance to really call the game," said Matsuzaka.

With the bases still loaded and nobody out, Matsuzaka got a strikeout and a popout to second, putting him in position to get out of the inning with the game still tied.

But Moore had other plans, slamming a meaty 2-2 fastball by Matsuzaka over the wall in right-center for a grand slam. Just like that, Matsuzaka was done for the night, and the Red Sox were staring at an 8-4 deficit.

"Nobody second guesses his will or his effort," said Francona. "It's bases loaded, he's having a tough inning. He's one 2-2 [pitch] on Moore from coming in the dugout, and we've got a tie game and he's going back out. One pitch later, you're starting to line up the bullpen and it's a long night."

The one horrific inning has been a recurring theme when Matsuzaka struggles.

"I don't think it's a physical thing," said Farrell. "That's indicated by the stuff he was throwing tonight. I thought he was strong tonight, but I think he relied a little bit too much on just throwing the ball, rather than pitching and hitting his spots and changing speeds."

Matsuzaka insists that the rigors of his first season on United States soil aren't taking any undue toll on him.

"I think all of us having fought so hard to get to this point of the season, I think fatigue is really a factor for everybody," Matsuzaka said. "To see everybody working so hard in spite of all that fatigue, I can't really use fatigue as an excuse for myself."

Things won't get any easier for Matsuzaka. His next start is against the Yankees on Friday, a team loaded with offense.

Perhaps in that one, Matsuzaka will go back to his wide variety of pitches.

"Yes," Matsuzaka said. "I think I have to use the pitches that I have."