Peralta hasn't manned the position since 2004 -- a season he spent primarily at Triple-A Buffalo. Until Thursday, he hadn't even taken ground balls at third with any intent of actually playing at the hot corner.
"I don't know how I'm going to do," he said. "I'll try to do my best."
Peralta is filling in at third on Friday because the Indians are without Andy Marte, whose season ended when he strained his left calf on Tuesday night. But the Indians might be open to the idea of moving Peralta to third permanently next season, if they acquire a second baseman and push Asdrubal Cabrera to his natural position at short.
Is that something they've discussed with Peralta?
"They don't say nothing to me like that," he said.
Peralta's limited range at short has been critiqued by fans, scouts and reporters. He's made 14 errors this season, after making 19 in 2005 and '07 and 16 in 2006.
Peralta has appeared in eight big league games at third, making three starts there in 2003 and one in '04.
He knows where he'd rather be.
"It's hard when you change your position," he said. "I want to play shortstop forever in my life. Whatever happens is their decision."
Anthony Castrovince is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.