Gardner's fleet feet were in the game as a substitution for those of Mark Teixeira, who had cracked his third hit to open the eighth inning against Angels starter Jered Weaver, a ground-rule double that cleared the right-field wall.
A walk to Alex Rodriguez brought on left-hander Darren Oliver, and manager Joe Girardi sent Gardner to second base with marching orders to take third base when possible.
"He knows why we put him out there," Girardi said. "We could leave the other guys out there if we wanted to play station to station."
With third baseman Chone Figgins playing off the bag, Gardner waited two pitches before dashing to third base, sliding headfirst before seeing the throw from catcher Mike Napoli skip into left field.
"I've had to make that throw, and it's a tough throw," Girardi said. "You're taught to throw it to the bag, but it's hard to throw it there sometimes when there's nobody there. And it just worked."
Robinson Cano added a run-scoring single to pad the advantage, giving closer Mariano Rivera a two-run lead to protect. Rivera secured his 40th save.
On a night when the Yankees and Angels seemed to be playing a postseason preview, Girardi's decision to insert Gardner in place of Teixeira was lauded as one that would have worked as well in October as it did in September.
"Tonight was Skip's game, making a great change in putting in Gardy for Tex," Nick Swisher said. "For him to get that stolen base and come into score, hat's off to Skip. Think about it -- just a great move in general, taking out one of your best hitters and bringing in a speed demon."
Not that the Yankees completely relied on speed and surprise. Swisher hit his 27th homer of the season to put New York on the board in the second inning, and Teixeira's two-run triple off the center-field fence in the fifth gave the Yankees a lead.
Teixeira's booming hit came after the Yankees had a run taken off the board, as Melky Cabrera was called for interference after colliding with Figgins on Johnny Damon's ground ball to the left side and sending Swisher back to third base.
But Teixeira made sure Cabrera's play didn't hurt the Yankees, sending home the go-ahead run on another odd play. Angels outfielder Torii Hunter lost his left shoe in pursuit of the fly ball, and Teixeira immediately pointed back toward catcher Jeff Mathis, wanting catcher's interference called for contact with his glove.
Had there been no contact, Teixeira thought, his hit might have cleared the wall, and he was originally angered thinking that Hunter would easily track down the ball.
As it turned out, Teixeira's first triple since Aug. 11, 2007, was plenty useful, as he ended just a homer shy of the cycle.
"He's been having a terrific season for them," Scioscia said. "And he's been doing a lot of things that we saw in half a year for us last year, and he's obviously had a big impact for those guys."
The support came after starter Joba Chamberlain turned in four innings of one-run ball in his fourth start under the revised "Joba Rules." Chamberlain used 67 pitches (41 strikes) in four innings, scattering four hits while walking none and striking out two in his longest outing since the Yankees altered their plan to lessen his workload heading into the postseason.
Vladimir Guerrero got the Angels started in the second inning with his 14th home run of the year, punishing Chamberlain for a hanging curveball by belting a high solo blast inside the left-field foul pole. But that was all the Angels would get off Chamberlain, who ultimately viewed the start as progress.
"You find a rhythm and want to continue to go, but we did everything we wanted to accomplish in this start," Chamberlain said. "I'll just continue to build and work on everything. It's just little mechanics here and there, and we're going to continue getting after it."
After Phil Coke worked out of a two-on, one-out situation in the seventh inning with the benefit of a snappy defensive play by shortstop Derek Jeter and Teixeira, the Angels tied the game in the eighth against Phil Hughes.
Bobby Abreu and Guerrero opened the inning with singles, and Hunter walked before Hughes got Kendry Morales to hit into a double play that sent home the tying run.
Girardi said that Hughes minimizing the damage in a bases-loaded, none-out situation might have been the turning point of the game.
"You'd like to get out of that without giving up a run, but obviously, with the bases loaded and nobody out, the chances of that are pretty slim," Hughes said. "I knew with the way we've been swinging, we'd have a chance to take the lead again."
Hughes couldn't have known it at the time, but he was setting up the Yankees to take one with a different kind of flair. Proving that they can beat the Angels at their own game could be a nugget that proves useful in the weeks to come.
"We know the teams that we're going to hopefully be playing in October, if we get there," Teixeira said. "The Angels are going to be one of them. You need to measure yourself up against the best."