"It's hard to say because we are several days away, but it looks like the natural fit," Rockies manager Walt Weiss said. "Jhoulys has to be re-evaluated, too. He just made a start, and he's going to have to throw a side and go through the routine that he has in between starts and make sure that he's OK."
Chacin went 1-1 with a 2.53 ERA in 10 2/3 innings over two games at Triple-A. He also pitched two games for Class A Advanced Modesto during his rehab stint.
"It's difficult to think four or five days ahead in this game because things chance on a daily basis," Weiss said.
Jesse Sanchez is a national reporter for MLB.com. Follow him on Twitter @JesseSanchezMLB. This story was not subject to the approval of Major League Baseball or its clubs.