"It's pretty sore today," Plouffe said. "I wouldn't be 100 percent to play today. But I don't think it's anything more than that. It's a bruise."
Arcia, meanwhile, said he tweaked his lower back while taking a swing in his final at-bat in Friday's game against the A's. He tried to take batting practice in the cage before Sunday's game, but he still had issues with his back and could hit the 15-day disabled list Monday if it doesn't improve.
"It's a little bit sore," Arcia said. "It feels better today."
With Plouffe out, Eduardo Nunez made the start at third base, while Chris Parmelee started in Arcia's place in right field.
Rhett Bollinger is a reporter for MLB.com. Read his blog, Bollinger Beat, and follow him on Twitter @RhettBollinger. This story was not subject to the approval of Major League Baseball or its clubs.