Darvish made his last rehab start on Sunday for Double-A Frisco, throwing 87 pitches. He is scheduled to start on Saturday against the Pirates.
"For me to have an extra day off to recover, that's going to help, too," Darvish said Wednesday. "I like having the extra day off."
Darvish had his final bullpen session on Wednesday, throwing 23 pitches as a tuneup for Saturday's start. It will be his first appearance in a Major League game since Aug. 9, 2014. He had the surgery on March 17, 2015.
"I'm very calm," Darvish said. "I'm very calmed down right now. "