"The big reason is all these extra innings we've had with our pitchers, and a couple are a little tender," Piniella said. "We're giving ourselves some extra protection there. I don't know how long we can stay this way."
He wouldn't identify who was "tender." The Cubs played five extra-inning games on their just-completed eight-game road trip. Angel Guzman and Carlos Marmol both pitched in six of the eight, Kevin Gregg pitched in five, and Aaron Heilman was in four.
The only extra bench players Saturday were infielder Andres Blanco, catcher Koyie Hill and outfielders Micah Hoffpauir and Reed Johnson.
"I think what you'll see early in the ballgame if we need to hit is we might use [Carlos] Zambrano," Piniella said.
Outfielder Ryan Freel, who is on the disabled list because of a strained hamstring, may be close to returning. He is scheduled to begin a rehab assignment Sunday or Monday at Iowa.
On Friday, Alfonso Soriano was moved to second base in the ninth in a double-switch, the first time he's played there since April 4, 2008, which also was for only one inning.
"I've got to be careful how we use our players," Piniella said. "You can run out of players very quickly."
Carrie Muskat is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.