Edmonds hit a shot off Milwaukee starter Dave Bush, and began taking awkward steps just before he reached third base. He limped the rest of the way home and returned to the dugout.
The Reds said Edmonds had a "strained right lower leg."
Edmonds started the season in Milwaukee before being traded to Cincinnati on Aug. 9.
It was Edmonds' second start since coming off the disabled list because of a strained right oblique.
He was playing at first base for Joey Votto, who was a late scratch because of a sinus infection. Miguel Cairo took Edmonds' place in the field.