Gardner, 26, won the center-field job in Spring Training, but he suffered through a slow start in April and quickly began losing time to Cabrera. In 248 regular-season at-bats, Gardner hit .270 with 26 stolen bases.
Though he has appeared in 12 of the Yankees' first 13 postseason games, Gardner has only five at-bats. He is 2-for-5 with a stolen base and three runs scored, and twice has been caught stealing.
If the Phillies force the World Series back to New York, it is likely Gardner will continue to start in center. The Yankees had spent their pregame hours Monday discussing a move to replace Cabrera, who has a left hamstring strain, on their active postseason roster before the Pena replacement move was officially announced. Jerry Hairston Jr. is the only other Yankees player to see time in center field, spending 15 innings there during the regular season.
"Gardy, defensively in center field, we like," Yankees manager Joe Girardi said. "Gardy is more of a center fielder [than Hairston]."
The other wrinkle in Monday's Game 5 Yankees lineup was that Jose Molina, for the fifth time this postseason and the 11th consecutive time overall, started behind the plate in a battery with A.J. Burnett.
The move, while expected, somewhat weakened a lineup that was already without Cabrera and designated hitter Hideki Matsui, confined to the bench in a National League ballpark.
While the top of the order -- Derek Jeter at shortstop, Johnny Damon in left field, Mark Teixeira at first base and Alex Rodriguez at third base -- remained constant, the bottom half of it shifted significantly for the first time in postseason play.
Nick Swisher, the right fielder, jumped up to fifth in the lineup against Phillies left-handed starter Cliff Lee, and the slumping Robinson Cano, just 2-for-15 in World Series play, fell to sixth. In the eighth spot was Molina, followed by Burnett.
Though he has used Jorge Posada as a pinch-hitter in each of the games Molina has started at catcher this postseason, Girardi said he would be hesitant to do so too quickly in Game 5 -- especially since his team is now carrying only two catchers.
Girardi, though, is well aware that Posada would like to be on the field for any potential World Series-clinching final out.
"It's difficult any time you sit down in the playoffs when you're a player and you're used to playing," Girardi said. "I can tell you that from experience, and I can tell you that just knowing Jorge Posada."
Anthony DiComo is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.