Twins trainer Tony Leo came out to look at Plouffe, who was able to walk off the field but was removed for Eduardo Escobar at third base in the bottom of the inning.
Twins manager Ron Gardenhire said Plouffe was being tested for concussion symptoms after the game but he hadn't heard the results yet.
"He got hit hard," Gardenhire said. "They're doing testing on him right now. He took a knee to the head and I think you guys all saw it. So they're doing testing right now and we'll know more later."
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.