Tino Martinez morphed from goat to hero with one swing of the bat yesterday in The Bronx.

Martinez erased from memory his bungling boo-boos from a night earlier with a home run yesterday against Oakland in a 5-0 Yankees win at the Stadium. The homer was Martinez’s fifth of the season and third in the past five games.

“Tino’s been swinging the bat well for me,” Torre said describing why he had Martinez batting sixth, behind and protecting Alex Rodriguez in the order.

Torre’s move paid dividends for both Martinez and A-Rod with the first basaeman clubbing a second-inning home run and Rodriguez chipping in with a double and three RBIs. Martinez went 1-for-4 with a couple of rockets to right and a groundout to go with his homer.

“I’ve been feeling really good at the plate, trying to have good at-bats and hit the ball hard,” Martinez said.

Friday night in the 6-3 loss to the A’s, Martinez was a big reason the Yankees dropped their fourth straight decision when he made a pair of fielding errors on the same play in the 10th inning. Martinez first booted a Scott Hatteberg chopper, missed tagging the bag, then threw wide of home plate. The two errors enabled Marco Scutaro and Jason Kendall to score, breaking the 3-3 tie with Mariano Rivera on the mound.

“Tino’s a gamer,” Torre said. “I’m sure he felt that in the back of his mind. When he makes an error on the defensive side of the game it’s unusual because he’s so good at what he does. So I’m sure he didn’t like the way the game ended, but no one else did, either. He takes on more blame on himself than anyone can place on him.

“I’m sure it felt good for him to do that,” Torre said. “He had some good at-bats today.”

Yesterday’s second-inning bop continued what had been a hot week for Martinez at the plate. He smashed back-to-back home runs Tuesday and Wednesday at Tampa Bay and went yard for the third time of the week yesterday against Oakland starter Joe Blanton for an early 2-0 Yankees lead.

Martinez turned on the first pitch he saw to lead off the second inning, depositing his fifth home run of the year into the right-field bleachers.