The 78-year-old former Dodgers great told reporters after the Friday incident he suffered no ill effects from the blow off the bat of Andre Ethier at Camelback Ranch in Arizona, MLB.com reported.
"I'm fine," Koufax said, adding, "It's more of a bruise. It feels more like a whiplash than anything. It's not even sore to the touch. I'm a little surprised."
The incident at the Dodgers' training facility sent a scare through the team, witnesses said. Koufax was struck while standing next to the bullpen along the left-field line.
"It didn't look good," Dodgers pitcher Clayton Kershaw told the website. "Glad he walked off. He seemed OK."
Koufax, a three-time Cy Young Award winner, was taken in a cart to the clubhouse to be examined. He returned about 10 minutes later after undergoing a precautionary computed tomography scan to rule out internal bleeding, MLB.com reported.