Los Angeles Dodgers left-hander Hyun-Jin Ryu has been scratched from Friday's scheduled start at Cincinnati because of stiffness in his back.
Chris Capuano will start for the Dodgers instead in the opener of a three-game series with the Reds.
Ryu, a rookie, is 13-5 with a 3.02 ERA and 139 strikeouts since signing a six- year deal with the Dodgers last December.
The Dodgers were in Denver Wednesday night to finish up a series against the Rockies. They are off Thursday.