Red Sox reliever Hideki Okajima is beside himself after giving up a grand slam to the Orioles’ Jay Payton in the seventh inning yesterday.

AP / Nick Wass

BALTIMORE — Today’s day off couldn’t come at a better time for the Boston Red Sox.

The Red Sox’ frustration was popping up like little brush fires all over Camden Yards yesterday as Boston wound up dropping a 6-3 decision to the Baltimore Orioles.

Former Red Sox Jay Payton provided the coup de grace, a two-out grand slam off Hideki Okajima in the seventh that wiped out Boston’s 3-2 advantage and tumbled the Red Sox to their fourth straight setback, fifth in the last six games, and a 4-6 record on the long journey through Detroit, Minnesota and Baltimore.

The frustration visibly spilled over in the eighth, when Manny Ramirez had to be restrained by first-base coach Luis Alicea after being called out on a close play by first-base umpire Mike Winters.

Ramirez, who appeared to have been safe on replays, flung his helmet to the ground and barked at Winters. Winters didn’t toss the Sox left fielder, but simply pointed to the helmet, indicating Ramirez would be fined for abuse of equipment.

Kevin Youkilis also began to get heated, though not nearly to the point Ramirez had, when he was called out at first on a bang-bang play as the Orioles turned a double play for the first two outs of the ninth.

There were quieter moments of frustration as well.

•Second baseman Dustin Pedroia not being able to come up with a spinning grounder to his left with two outs in the seventh, setting up the events that led to Payton’s slam.

•Reliever Craig Hansen unable to retire either of the two batters he faced in the seventh.

•Okajima’s performance. He has now allowed a whopping 11 of the 14 runners he has inherited to score, the worst ratio for a reliever in the league, not to mention his fourth blown save in five opportunities despite an earned-run average of 0.93.

The late Orioles’ eruption deprived Jon Lester of a well-deserved win. The left-hander blanked Baltimore until the sixth, when the Orioles tallied two runs. That prompted pitching coach John Farrell and interim manager Brad Mills, the bench coach who took over for manager Terry Francona (death in the family), to go to the bullpen in the seventh even though Lester had thrown only 86 pitches.

“We did lose five out of six, but we battled,” Mills said. “He had thrown about 30 pitches (32, actually, in the sixth) and with where they were in the order, we thought we had the best bullpen matchups.”

For two outs with Javier Lopez on the mound, the plan worked well. Then Freddie Bynum hit a grounder to the right side off Lopez. And Pedroia, sliding to his left on the outfield grass, just behind the dirt portion of the infield, couldn’t come up with it.

“I had the lip (of the grass) right there and the ball was spinning,” Pedroia said. “I slid for it so in case it hit the lip I’d have my body in front of it. I got my glove on it, but my knee hit my glove and knocked it out. That’s a tough play, but I can make that play.”

No one was second-guessing Pedroia or fingering him for any blame.

Besides, there were two outs and one on. Out went Lopez, in came Hansen, who was spared a demotion a few days ago, when the Sox designated Julian Tavarez for assignment.

He gave up a solid single to right to No. 9 hitter Guillermo Quiroz and then walked Brian Roberts on a 3-and-2 pitch.

“I was pushing the ball a little too much instead of trying to throw it through the plate,” sighed Hansen. “When I do that, my control is not the best.”

Out went Hansen. In came Okajima.

After Payton fouled off his first pitch, a changeup, Okajima served up a splitter to Payton’s liking, and he drilled it on a line over the fence in left. The pitch wasn’t down enough or in enough.

And how did Okajima feel about that? Who knows? He informed his translator, Jeff Yamaguchi, that he didn’t have anything to say about it and wouldn’t talk to the media.

Catcher Jason Varitek, whose solo homer in the fifth helped Boston take a 3-0 lead, gave Payton credit.

“I know he sat on that pitch, look for it, got it closer to him and hit it,” said Varitek of Payton, a fellow former Georgia Tech star.

Nothing good happened after that, but it could have been worse if coach Luis Alicea hadn’t gotten between Ramirez and Winters.

Said Ramirez calmly after the game, “I thought I was safe. Watch the replay. I was a little mad.”

So maybe getting away from the park can help the Sox, who will open a three-game series at home against Milwaukee tomorrow night.

“We’ve had a tough stretch,” Pedroia said. “We have to get a good day off and get ready for the next series and play better baseball.”

skrasner@projo.com