Miguel Cairo replaced Valdez, leaving only Ryan Ludwick, Chris Heisey and Dioner Navarro on the bench against the Padres. Pitcher Mike Leake was also available to pinch-hit.
Phillips was likely unavailable because of a strained left calf, but his injury hasn't been considered serious enough to warrant a trip to the disabled list. Scott Rolen, who normally gets day games off following a night game, made the start at third base since backups Todd Frazier and Cairo were already playing other spots.
"Yeah, we're real short. We were short [Wednesday]," Reds manager Dusty Baker.
There was little improvement to report from Valdez.
"Not much," Baker said. "It'd be a better chance if we had a night game tonight vs. a day game after night. It hurts him to slide, that's when you get jarred. That's when it goes up and down your vertebrae."