With Iowa this season, Maine is 1-0 with one save and a 1.42 ERA (1 ER/6.1 IP) in five relief appearances.
The 27-year-old Maine has no record and a 4.95 ERA (11 ER/20.0 IP) in 20 major league relief appearances covering the last two seasons with the Cubs. He made his big league debut in 2010, posting a 2.08 ERA (3 ER/13.0 IP) in 13 outings before recording a 10.29 ERA (8 ER/7.0 IP) in seven appearances last year.
Maine spent most of the 2011 campaign with Triple-A Iowa, where he went 3-4 with 12 saves and a 3.68 ERA (21 ER/51.1 IP) in 38 relief outings. He struck out 72 batters and walked only 25 in 51.1 innings pitched.
The southpaw was originally acquired from Arizona on November 19, 2009 in the three-player deal that sent righthander Aaron Heilman to the Diamondbacks.
Wood is 0-1 with an 11.57 ERA (3 ER/2.1 IP) in four relief appearances for the Cubs this season. He last appeared a week ago in St. Louis on April 13, retiring the lone batter he faced.