"I felt great," Duffy said. "Everything went fine. We'll see how it feels [Friday], but I should be good to go. I can't wait. Believe me. I need to get back out there and help the boys."
Duffy, recovering from a low-grade pronator (forearm) strain, also is eager to wipe out some bad memories at Progressive Field.
Earlier this summer, Duffy was forced to go on the DL because of an oblique injury sustained while trying to cover first base on a throw at Progressive Field.
During the Royals' last visit here in late August, Duffy left the road trip early because of pain in his forearm area, and he returned to Kansas City for an MRI exam that revealed the pronator strain and again forced him to the DL.
"Cleveland hasn't been very good to me so far this season," Duffy said.
Royals manager Ned Yost said Duffy likely would be on a pitch count Sunday if activated, but didn't reveal specifically what that number would be.
Jeffrey Flanagan has covered the Royals since 1991, and for MLB.com since 2015. Follow him on Twitter @FlannyMLB. This story was not subject to the approval of Major League Baseball or its clubs.