Damon hit a tiebreaking homer and New York received lights-out relief pitching from rookies Joba Chamberlain and Edwar Ramirez, sending Chien-Ming Wang and the Yankees to a 9-3 victory over the Detroit Tigers.
"We have guys who understand this is crunch time, guys who know how to flip the switch," Damon said. "Winning three of four from Detroit -- that's no small task."
With his 1,149th win as manager of the Yankees, Joe Torre tied Hall of Famer Casey Stengel for second place on the franchise list behind Joe McCarthy (1,460).
Damon, banged-up much of the season and not starting as often as he'd like lately, finished with three hits to help New York win for the 15th time in 20 tries. The Yankees (70-54) equaled a season high at 16 games above .500.
"It was another test. The season is all about testing yourself," Torre said. "We have a lot of confidence in ourselves."
Playing without Derek Jeter, given a rare day off, the Yankees took advantage of an error by slick-fielding third baseman Brandon Inge in the fifth and broke it open on Betemit's three-run double off Aquilino Lopez with two outs in the eighth.
Betemit started at shortstop for Jeter and played a big role as New York improved to an AL-best 27-11 since the All-Star break. The Yankees, right in the thick of a close wild-card race, moved within four games of first-place Boston in the AL East.
That matches the closest they've been since the morning of April 25. New York also was four out after beating Baltimore last Monday, before losing three in a row.
"We have a lot of good things going on," Damon said.
The Tigers, who have dropped eight of 12, fell to 15-23 since the break. They remained 1½ games back of first-place Cleveland in the AL Central.
"We're striking out way too much. When you get the starting pitcher in trouble in the fourth or fifth inning, you've got to put the ball in play," manager Jim Leyland said. "Bad at-bats with men in scoring position."
The Yankees open another big series Monday night with the first of three games at the AL West-leading Los Angeles Angels, a longtime nemesis.
Detroit heads home for three key games against the Indians starting Tuesday, then hosts the Yankees four times next weekend.
"I just think you go through hot and cold streaks during the course of the year," said ex-Yankee Gary Sheffield, booed loudly all weekend. "Unfortunately, we're going through a cold streak right now."
Wang (14-6) limited damage by pitching out of trouble in several crucial situations. Rebounding from consecutive rough outings, he allowed three runs and nine hits in six innings.
Chamberlain and Ramirez combined for three perfect innings to finish it.
Jeremy Bonderman, who shut down the Yankees last October to seal Detroit's first-round playoff upset, fell to 0-5 in his last seven starts. Bonderman (10-6) walked five batters in six innings.
With the delirious sellout crowd of 55,071 chanting his name again, Chamberlain worked a perfect seventh against the middle of Detroit's dangerous lineup. He induced Sheffield to pop up on an eye-high, 99 mph fastball, then struck out Magglio Ordonez and Carlos Guillen to preserve a 4-3 lead.
"I still get chills every time it happens," Chamberlain said. "I'm going to challenge every guy out there."
The rookie sensation has 11 strikeouts in seven scoreless innings since being called up from Triple-A on Aug. 7.
"For someone of this limited experience, I can't remember anybody like him," Torre said. "Not only as far as throwing hard, but the fact that he can make pitches."
Ramirez struck out all three batters in the eighth, then worked a 1-2-3 ninth for his first career save.
With the score tied at 3-3 in the sixth, Damon hit a solo shot into the right-field upper deck off Bonderman for his first home run since July 31.
- Wang is 4-0 with a 2.90 ERA in five career starts against Detroit.
- The Yankees have won 11 of their past 13 series and seven consecutive four-game sets, all 3-1, according to the Elias Sports Bureau.
- All-Star 2B Placido Polanco (flu) of the Tigers missed his sixth consecutive game as he tries to regain his strength.
- Detroit C Ivan Rodriguez received a scheduled rest to give him consecutive days off.