Tino Martinez is getting extra workouts lately – from all the dugout stairs he’s been climbing to take curtain calls.

The Yankee first baseman crushed another home run last night in the Bombers’ 4-3 win against Seattle, bringing his total to five in his last six starts.

He’s also homered in three straight games.

So what’s his secret? Why has he been seeing the ball so well?

“Sorry,” Martinez said as he made his way out of the Yankee clubhouse. “I don’t have all the answers, man. I wish I did.” He may not have answers, but Martinez does have one thing: the hottest bat in the Yankees’ powerful lineup.

“Tino’s been swinging the bat well,” Derek Jeter said.

Good thing for the Yankees, too, since Jason Giambi – expected to split time at first base and DH with Martinez this season – has been so dreadful.

Manager Joe Torre recalled calming a then-struggling Martinez during spring training, telling him, “Numbers may not be significant to think about because you’re only going to play three or four times a week.”

But that hasn’t been the case. Last night, against one of his former teams – Seattle – No. 24 started for the 25th time at first, going 1-for-3.

Giambi started four games there this season.

“I just wanted to put that in his head so he doesn’t think he’s playing for playing time,” Torre said of that spring talk with Martinez. “But again, Jason is struggling and has some problems physically, so he [Martinez] has been a godsend for us.”

Martinez’ homer last night, his seventh overall, was a two-run shot to right in the fourth inning against Seattle starter Gil Meche on a 2-2 fastball. It gave the Yankees a 3-1.

“I’ve just been having good at-bats,” Martinez said.

“I believe in myself. I’ve been around a while and I expect to do my part, do my job and produce.”