Alex Rodriguez and Jorge Posada each homered twice, and the surging Yankees routed the Detroit Tigers 12-3 last night behind Mike Mussina to move three games over .500 for the first time this season.

Robinson Cano hit his first major league homer and Gary Sheffield also connected, proving that his sore left hand is healthy enough for him to hit. The Yankees (24-21) finished with a season-high six home runs, four off starter Wilfredo Ledezma, and won for the 13th time in 15 games.

Mussina (5-2) allowed six hits in seven shutout innings, winning his fourth straight decision in a span of five starts. He improved to 16-5 against the Tigers.

Even on a windy, 48-degree night in the Bronx, New York’s hitters warmed up quickly, scoring at least 10 runs for the seventh time this season.

Posada homered from both sides of the plate for the sixth time in his career and drove in four runs.

Rodriguez increased his major league-leading total to 16 homers with the 39th multihomer game of his career, the third this season. He also walked, scored three times, and knocked in three runs. Rodriguez now has 397 career homers, surpassing Joe Carter for 42nd place all-time.

Rodriguez, who also leads the big leagues with 46 RBI, was plunked near the hip by Franklyn German in the seventh, a pitch that appeared to be intentional. A-Rod jogged to first without a problem, then was removed from the game just as several other Yankees regulars already had been.

Paul Quantrill retaliated in the eighth, throwing behind Jason Smith and then hitting him with a pitch in the back. That brought the Tigers out of their dugout, and Quantrill egged them on, gesturing for them to come out for a fight.

But the Yankees never left their bench, and order was quickly restored with no punches thrown. Quantrill and manager Joe Torre were ejected.

Buddy Groom came on and gave up a three-run homer to Marcus Thames.

Rodriguez homered to right-center off Ledezma (2-4) in the second and added a two-run shot in the fourth. Posada followed with a drive to left, making it 4-0. Jason Giambi then singled, Bernie Williams doubled and Cano delivered a sacrifice fly.

Sheffield hit a two-run shot in the fifth for no. 422 of his career, chasing Ledezma. Hideki Matsui doubled off Matt Ginter, Rodriguez walked, and Posada connected for a three-run homer from the left side.

Cano homered into the right-field upper deck off Doug Creek in the eighth.

The Yankees’ six homers tied their most ever at Yankee Stadium.