Alfredo Aceves gave up four runs in the ninth, including the game-winning three-run homer by Joe Mauer. (AP)

The Red Sox were one out, one strike from victory.

Closer Alfredo Aceves thought he had Joe Mauer on a 2-2 fastball away. But home plate umpire David Rackley did not ring up the former AL MVP, and so, with the Red Sox clinging to a 4-3 lead and Twins runners on second and third with two outs, Mauer had a new lease on life. On the full-count offering, Mauer unloaded on another fastball from Aceves, depositing his seventh homer of the year just over the Green Monster for the decisive three-run homer in Minnesota’s 6-4 victory.

The homer was a crushing blow to the Red Sox, who had just taken the lead the previous half-inning on a Pedro Ciriaco pinch-hit home run and then added an insurance run. Instead of emerging with an emotional win, Boston fell hard to a seemingly impossible new low for the 2012 season.

The sequence was made even more heartbreaking for the Red Sox thanks to the 2-2 offering, a 95 mph fastball that came very close to the outside corner. Asked whether Mauer’s homer simply represented a poorly located pitch, the closer noted, “I think [the 2-2 pitch] was a strike. … Why don’t you ask the umpire how he missed the pitch before? Ask him,” said Aceves. “It’s part of the game, mistakes. And also I make a mistake the next pitch and that’s it. It cost us the game.”

Aceves had actually given the Sox a shot to mount their rally in the eighth. He inherited a bases-loaded, no-out jam from Andrew Miller in the top of the eighth inning, at a time when the Sox were leading, 2-1. While Aceves allowed the tying run to score on a sac fly, he minimized the damage and with runners on the corners and one out, stranded the two runners to preserve the tie, setting the stage for the Sox to rally and take a 4-2 lead in the bottom of the eighth.

But in the ninth, the Twins hit him all over the park, as Aceves permitted a double and RBI single with one out and then, after a fly out, permitting a two-out single and wild pitch to put runners on second and third for Mauer. The last offering of Aceves’ 34-pitch, 1 2/3 inning effort led to the game’s final outcome, but a case can be made that it was the Red Sox closer’s 33rd pitch of the night that was decisive.

Kelly Shoppach thought that the pitch was right on the edge of the plate as well, but he did not say it was a mistake from the umpire.

“You know, 2-2 was really close. Right on the edge. I thought it could have went either way. And then the 3-2 was just a mislocated fastball,” said the catcher.

The 29-year-old closer is 2-7 with a 4.37 ERA after the loss, and he has allowed a home run in each of his last two appearances. Before the last two outings, Aceves had a 3.57 ERA and 22 saves, including a career-long nine-game scoreless appearances immediately preceding his two rough outings against the Twins.

“He has thrown the ball great for us all year and has pitched in some really tough spots,” Shoppach said. “It’s not too many times you see your closer throw three innings at a time and he has done that a few times for us. We feel good with him out there on the mound. He’s got plenty of stuff to get outs, it just didn’t work out tonight.”

Aceves vowed that he would not dwell on his defeat.

“Every game is important. And whatever game is done is done,” said Aceves. “I’m healthy. I’m not going to frustrate myself. For what? Nothing about that, buddy. I’m not frustrated. I have health. I have my parents. They’re really cool.”