"That last pitch he threw me, at 99 mph, is not supposed to move like that," said Swisher.
And when Bard faltered a bit in the eighth, giving up a mammoth bomb to Mark Teixeira and then allowing two more baserunners, Jonathan Papelbon was called on to register the game's final four outs.
Papelbon did just that, producing save No. 28 on the season with some of the most overpowering stuff he's had all season.
"I felt good," said Papelbon. "I think if I can put my body in a position to be at its best, my pitches are going to be at their best. I think that goes hand in hand. I felt good today. I would say that was one of the better days I've felt this year."
And with the win, the Sox chipped their deficit back to six games in the American League East, the same as it was when they arrived in New York. They are 4 1/2 games behind the Rays in the Wild Card standings.
"A lot of good things happen today or we don't win that game," said manager Terry Francona. "We didn't have a lot of runs and we made it hold up. Like I said, that was one of the funnest days. That was a good day of baseball."
While pitching carried the day for the Sox, Jacoby Ellsbury also had his best game since returning from the disabled list. He went 1-for-2 with a walk, snapping an 0-for-16 drought. And the speedy center fielder set a career-high of four stolen bases, tying Jerry Remy's team record, set on June 14, 1980.
A fruitful day in the bank for the visitors, the Red Sox and Yankees parted ways until Sept. 24, at which time the rivals again meet up in the Bronx.
"If their pitching staff is healthy, that's all that matters," said Teixeira. "Pitching is everything in this game, and their starting five is as good as anyone's in baseball. They have arguably the best eighth-and ninth-inning guys in baseball as well. That combination is really tough. You put that together with a lineup where a guy like Mike Lowell can hit seventh, that's a good team. I don't care how many injuries they've had."
Though the Red Sox scored a total of just six runs over the final three games of the series, Francona's team did jump out first in the finale. Just after Lowell had been robbed of a hit on a brilliant diving catch in right by Swisher, Ryan Kalish hit a single to right, stole second and advanced to third when Jorge Posada's throw sailed into the outfield.
Bill Hall stepped up and hit a hard grounder into the hole that Jeter couldn't make a play on to score Kalish to make it 1-0. Ellsbury ended his 0-for-16 drought since returning from the DL by looping a liner over the head of Jeter. Marco Scutaro drew a walk and J.D. Drew hit a fielder's-choice grounder to second to give Boston a two-run edge.
Coming into the contest, Lester's recent slump -- a career-high losing streak of four games -- was a storyline only because it was unusual. But he was back in top form in this one, stifling the Yankees with 6 1/3 shutout innings. He allowed four hits and three walks, striking out six. Lester improved to 12-7 and lowered his ERA to 2.94.
"It's huge," said Lester. "Any win this time of year is big for us. Obviously being in here makes it a little more special. [We] just keep chipping away."
The lefty had a no-hitter until the fifth, when Austin Kearns hit a one-out single up the middle.
While the Red Sox failed to add on offensively despite a running attack that produced five stolen bases, the Yankees finally produced a full-fledged threat in the bottom of the seventh. Posada (single), Marcus Thames (double) and Kearns (hit by pitch), pinning Lester in a bases-loaded nobody-out jam.
But Lester mowed Curtis Granderson down on four pitches, striking him out on a 78-mph curve.
With the dangerous Jeter looming, Francona didn't even blink before calling on Bard. This is the situation the Red Sox feel the flame-throwing righty is made for.
The results were, well, flawless. Not only did Bard strike out Jeter on three pitches, but he did the same to Swisher. It was one of the most impressive escapes of the season for Bard, who has a 1.90 ERA.
"Yeah, I mean, it's kind of win-win," said Bard. "Just give it your best shot, and fortunately, I was able to bail Jonny out. He pitched a great game and deserved a win there. I'm glad we could hold it for him."
Then there was Papelbon, who came on to hold it for Bard. With runners on first and second and two outs in the eighth, Papelbon got Kearns on a first-pitch groundout.
Jeter kept hope alive for the Yankees with a one-out walk and moved himself into scoring position by stealing second. But Papelbon was explosive with his fastball and nasty with his splitter, striking out Swisher and Teixeira to end it.
"To come in here and split, not that we're satisfied with it, but against this team, in this situation, given how many guys we're missing, we've kept ourselves where we need to be," said Bard. "Maybe we get them back in our park later on and make a real run, but we've given ourselves a chance."
And at this point of the season, with everything they've gone through, the Red Sox can't really ask for more than that.