Vargas underwent an appendectomy on July 9 when the club was at Tampa Bay for a series.
"He feels it, but it's OK," Yost said.
Vargas has been replaced by Bruce Chen in the rotation for next Tuesday night's game at Chicago, but might Vargas be ready for the next turn after that?
"Maybe. He could, then again he could not, might not," Yost said.
Dick Kaegel is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.