Danks believes the soreness stemmed from his first minor league rehabilitation start on Tuesday at Columbus, when he threw four innings and 61 pitches.
"I think it’s because I amped it up and pushed it the other day, which is good," Danks said. "It’s what we needed to do. But it’s pretty sore. I went out and played catch. It was sore."
Danks hasn't pitched for the White Sox since May 19.