Pearce was acquired by the Yankees from the Houston Astros for cash considerations on Monday, shortly before slugging first baseman Mark Teixeira strained his left calf. He arrived Tuesday, in time for batting practice.
Teixeira says he still thinks the injury will keep him out at least a week.
Manager Joe Girardi said he had Pearce batting cleanup because he didn't want to disrupt his top three in the lineup and the right-hander hits well against lefties.
The Yankees optioned Casey McGehee to Class-A Charleston. The South Atlantic League team's season ends Sept. 3 which will allow McGehee to return sooner.