BOSTON — There’s never a dull moment for Doug Mirabelli behind the plate.

At the plate, well, that can be a very different — and not usually anywhere near as exciting — situation for the Red Sox’ designated (for Tim Wakefield and his knuckler) catcher, who came into yesterday’s game at Fenway against the Orioles batting .183.

But it proved to be an eventful afternoon for Boston’s backup backstop.

It’s always an adventure for Mirabelli when he has to try to corral Wakefield’s dancing, fluttering, unpredictably dipping and diving deliveries.

“It’s never the same,” Mirabelli said. “That’s the nature of the pitch. That’s why it’s so effective.”

Wakefield was very effective through the first four innings before squandering a 3-0 lead when he was tagged for three runs on four hits in the fifth. But he retired the Orioles in order in the sixth, striking out the first two batters, and then Boston loaded the bases with one out in the bottom half of the inning.

Mirabelli, who had lined his fourth homer of the season off the top of the Green Monster in the fourth, was on third base following a leadoff single, and appeared to be about to score the go-ahead run when David Ortiz lofted a fly ball to the warning track in front of the visitors’ bullpen in right field.

Except that, after tagging up and starting toward home, Mirabelli felt he had left too early, and returned to third. By the time he again was headed toward the plate, the ball was well on its way. Second baseman Brian Roberts’ relay of Nick Markakis’ toss from the track easily beat Mirabelli home, where he was tagged out by Paul Bako in an inexcusable rally-killing, inning-ending double play.

“I tried to get a good jump,” Mirabelli said later in the clubhouse. “It’s something I didn’t really need to do, considering the distance that ball traveled, but I’m not really fast and, regardless of how far a ball is hit, it’s not easy for me to score.

“It’s hard to make two mistakes running the bases on one play,” he added, “but I did. The first was leaving too early, when I didn’t have to. The second was going back, and then trying to come home after that.

“It was embarrassing. I could easily have cost ‘Wakey’ a win. If I’d cost him a win over a dumb error like that, it would have been tough to face him. It would have been tough to face everybody in (the clubhouse.)”

Fortunately for Mirabelli, he had a chance to save face the following inning.

With two outs and runners on first and second, he hit a soft fly ball that fell into center field for his third hit of the game — the first time he’d had that many in almost three years — and scored Coco Crisp with the go-ahead run.

The Sox went on to score four times in the inning, notching a 7-4 win that improved Wakefield’s record to 13-9.

“We were thrilled that Dougie came through,” Sox manager Terry Francona said. “I think we’re probably one of the few teams where, if something like that happens, you don’t see a lot of tension in the dugout. We don’t want to make mistakes, but we were very hopeful we would overcome and win like we did.”

Mirabelli said he was more relieved than thrilled when he made up for his base-running gaffe with his clutch hit.

“I felt like I had to come through in that situation,” he said. “If I didn’t, I’d have felt like I’d really let the team down. To get the hit that put us ahead feels good, but, honestly, I feel more relieved than anything.”

Mirabelli comes off the bench to relieve regular catcher Jason Varitek whenever Wakefield pitches. Of Mirabelli’s 26 starts this season, 21 have come when Wakefield was on the mound, and he has been behind the plate for Wakefield’s last 39 starts, going back to May 2006, when he was reacquired from the Padres, after having been traded to San Diego the previous December.

“Catching the knuckler is tough,” said Mirabelli, “but it’s in my job description.”

What’s tougher than what he does behind the plate is trying to hit consistently, given that he plays sporadically — usually getting to the plate only every five days or so.

“I work hard to do the best I can out there,” he said. “It’s tough when you’re not playing that much.”

“He’s got a real good understanding,” Francona said, “that you can’t walk up there and look at your batting average when you’re playing every five days. He’s done a very good job, and always has, of handling that. When he gives us offensive punch, it’s great.”

Mirabelli had just 93 at-bats prior to yesterday’s game, with three homers among his 17 hits, and a total of 11 RBI.

He walked in his first trip to the plate, in the second inning, then hit the first pitch thrown to him in the fourth on a line over the left-field wall.

“It was a first-pitch fastball,” he said.

Mirabelli singled to start the Boston sixth, but then brought the inning to an abrupt, and disappointing, end with his base-running blunder.

He more than made up for that, though, with his run-scoring single in the seventh.

“It was just one of those days,” he said. “I haven’t had too many of them. I felt good at the plate. It makes you feel good to help the team.”

jdonalds@projo.com