Damon's go-ahead drive off Baltimore's Jim Johnson helped secure a series victory for the Yankees, accounting for his fifth homer in seven games, continuing a stretch that has seen him hit .419 (13-for-31) after working on mechanical tweaks with hitting coach Kevin Long.
"I'm just thinking about driving the ball, getting leverage and getting lift on the ball," Damon said. "It's been a nice run. Hopefully we can still have it once this off-day passes us and I can continue to do that kind of stuff."
The homer erased the sting of another troublesome first inning from Chamberlain, who has had trouble getting his juices flowing until deeper in his outings. That left him prone to retribution in the first inning, when Aubrey Huff belted a three-run homer and punctuated the shot with a pair of exuberant gestures.
Huff celebrated as he rounded the first base bag, looking directly at Chamberlain and shouting as he pumped his right fist. Huff did the same after touching home plate, showing off with more authority as he accepted greetings from Brian Roberts and Adam Jones, who were aboard for the shot.
Chamberlain's fist pumps have been a topic of conversation around the league since he debuted in 2007, and the Baltimore clubhouse has been no exception. Huff made no secret of the fact that he acted with Chamberlain in mind, coming into the game 1-for-8 against the 22-year-old with three strikeouts.
"He's done it a couple of times to me when he's struck me out," Huff said. "For me, it's just in good fun. I always told the guys that if I get him, I'm going to give him a nice fist pump. For me, it wasn't really showing anybody up. I was just trying to have some fun with it. He does it all the time and I figured, 'You know what, why not?'"
Girardi said that he would have no comment, and Chamberlain -- whose back appeared to be turned when Huff rounded first base -- said he "honestly didn't see it," but noted cryptically, "This won't be the last time I face him."
"He did what he was supposed to do with the pitch -- he hit a home run," Chamberlain said. "If he wants to do a back flip, he can do a back flip. It really doesn't bother me."
What does bother Chamberlain is that, through six starts, he has allowed nine first-inning runs and three home runs, with opponents hitting .481 (13-for-27). His first-inning issues with velocity continued Sunday, as his fastball ranged mostly near 90 mph before gaining speed later.
"I've always been a slow starter. Always," Chamberlain said. "It's something I've been trying to figure out for a long time. We need to figure it out soon, because it's frustrating and it's starting to make me mad."
The Yankees were worried by the sluggish opening -- and Chamberlain's battle with a busted blood vessel in his thumb -- enough to have long reliever Alfredo Aceves warming as early as the second inning.
Girardi called the situation "dangerous" and said they would use Monday's off-day to try and iron it out after the team lands in Toronto, where they open a three-game series on Tuesday.
"I think it's something we have to address until we find the perfect formula," Girardi said. "I can't tell you if it's mental or if it's necessarily physical. I just know it seems that in the first inning, his stuff is not as good. It happens to a lot of guys and you try different things to find a way."
Phil Coke hurled two scoreless innings and Mariano Rivera locked down the ninth inning for his sixth save, easing concerns about diminished arm strength after allowing the first back-to-back homers of his career on Thursday to the Rays.
"His stuff seemed much better than what we saw before," Girardi said. "His ball was lively and running a lot. The cutter was very good and the velocity was better. I felt a lot better."
Mark Teixeira also homered for the second successive game, slugging his seventh of the season to center field in the first inning. It was the only run the Yankees would get off right-hander Koji Uehara, who scattered six hits over six innings, walking none and striking out five.
Robinson Cano cut the deficit to one run in the seventh with a solo homer off reliever Jamie Walker. The inning progressed as Francisco Cervelli beat out a ground ball and Derek Jeter legged out an infield hit before Damon connected on his drive to right field, doing so wielding a pink bat in honor of Mother's Day.
"The inning doesn't continue unless Cervelli beats that ball out," Chamberlain said. "He's been doing a fantastic job and Johnny just continues to be Johnny like he has his whole career, coming up with big hits when we need them."