The Arizona Diamondbacks activated Joe Saunders off the 15-day DL, and Saunders took the mound Saturday afternoon against the Cubs. 

Saunders went into Saturday's action with a 4-5 record, a 3.44 ERA in 13 starts, and 53 strikeouts in 81 innings pitched. 

Saunders ended up throwing six innings against the Cubs, allowing three earned runs on eight hits, while striking out four batters and walking none. 

In a corresponding roster move, the Diamondbacks optioned Patrick Corbin to Triple-A Reno. The left-handed Corbin was pitching out of the bullpen since being recalled, and leaves for the minors with a 4.15 ERA in 39 innings pitched. 

Josh Collmenter was filling in for Saunders in the rotation, and he'll move back to the Arizona bullpen. Collmenter has a 4.11 ERA in 57 innings pitched, and his 3.71 K/BB rate is one of the best on the team.