Ramirez did appear in the game, inserted as a pinch-runner in the ninth inning of Miami's 4-3 loss.
The hand, which Ramirez initially injured on July 8 by hitting a cooling fan in frustration, began showing signs of infection on Thursday evening, manager Ozzie Guillen said.
"The hand was pretty ugly, and pretty sensitive," Guillen said. "You have to be careful."
The infection reportedly is a result of Ramirez not taking his prescribed antibiotics.
When asked about it, Guillen said, "That's what I hear.
"How do you forget to take a pill that doctors [tell] you to take?"
Greg Dobbs filled in for Ramirez at third base, hitting sixth. Dobbs is batting .301 with two home runs and 22 RBIs over 63 games.
Ramirez, a three-time All-Star, had appeared in every game but one this year before Friday. He has a .248 average, with 12 long balls and 44 RBIs.
"Hopefully, he can play [on Saturday]," Guillen said. "It was pretty nasty.
"I thought something bit him."