Manager Terry Collins checked the clubhouse for volunteers and came up with Mike Baxter, who caught in the Padres' organization in the 2008 Instructional League.
"I caught down there," said Baxter, who said he has a catcher's mitt, but doesn't have it with him on the road trip.
Beyond Tuesday, Collins plans to see how Nickeas feels.
"If he's not better, we've got to find somebody," said Collins, who would look to perhaps bring up a Minor Leaguer as early as Tuesday night.
Collins added that he's been pleased with how Baxter has looked at the plate in his rookie season.
"Mike's been swinging the bat real well, that's why I'm I hitting him where [he is]," Collins said. "The way he's been swinging [the bat] that if they pitch around Ike [Davis], he can do some damage."