NEW YORK -- Yankees rookie Brett Gardner stood in the batter's box in the bottom of the 10th inning Sunday night with the potential to be the hero.

There were two outs. There was a runner on second base. Red Sox closer Jonathan Papelbon was on the mound.

Gardner, who made his major-league debut last Monday for the Yankees, was thrust into the starting lineup on Friday when teammate Johnny Damon injured his left shoulder attempting to make a catch against the fence. He finished Friday's game in left field and started both Games Three and Four of this series against the Red Sox.

Sunday night his was 1-for-4 before he faced Papelbon in the 10th inning. It was the hard-throwing right-hander versus the rookie.

The rookie won.

Gardner's RBI-single up the middle proved to be the game-winner as the Yankees won, 5-4. As a result of the victory, the clubs split the series.

"That was the biggest at-bat of my life right there," said Gardner. "It feels good because we lost the first two games to these guys, and after you win Game Three you want to come back and find a way to win Game Four. I'm just glad we were able to get it done."

Even Red Sox manager Terry Francona gave the rookie his due after the game. Gardner kept fouling off pitch after pitch until he delivered his game-winning hit on Papelbon's eighth offering.

"Pap made some good pitches and the kid fouled off some good pitches," said Francona. "He puts the bat on the ball in a spot where Alex Cora is doing everything he can to keep the ball in the infield, but it just glanced off his glove."

When Damon slammed into the left-field fence on Friday and was taken out of the game, Gardner was given the nod by manager Joe Girardi. Gardner, a third-round selection by the Yankees in the 2005 draft, said he just wanted to keep things simple.

"You need to treat it like any other game," said Gardner. "I just need to treat it like I was doing down in Scranton (with the Triple-A Scranton/Wilkes-Barre Yankees) and I feel good about what I'm doing up here. I need to see the ball good and find ways to get on base and help the team out."

Even facing a pitcher like Papelbon with the game on the line didn't seem to faze the rookie, especially given the type of at-bat he produced.

"That's what you get with Yankees-Red Sox," said Gardner. "You know he's going to be in there late for them, and [Mariano Rivera's] going to be in there late for us. I faced him a couple of nights ago and it's good to know what a guy has. I saw all fastballs the other day and every pitch (Sunday) was a fastball except for that last one."

Papelbon's last pitch was a splitter that Gardner smacked up the middle to give New York the victory.

"You have a guy 0-2 and you figure you can put him away," said Papelbon. "It didn't happen."