The 29-year-old Schlitter went 2-3 with a 4.15 ERA (26 ER/56.1 IP) in 61 appearances for the Cubs last season, his first big league action since the 2010 campaign. He turned in a 2.98 ERA (14 ER/42.1 IP) in 43 appearances prior to the All-Star Break before being slowed by right shoulder inflammation that led to a stint on the disabled list in August. Overall, he allowed one earned run or less in 54 of his 61 appearances, including 48 scoreless outings.
Schlitter was originally selected by the Philadelphia Phillies in the 16th round of the 2007 Draft and acquired by the Cubs the next season for lefthander Scott Eyre. Schlitter made his big league debut in 2010 with seven relief appearances. He is a native of Oak Park in suburban Chicago.
Grimm, 26, had yet to appear in a game for the Cubs this season. He went 5-2 with a 3.78 ERA (29 ER/69.0 IP) in 73 relief appearances for the Cubs last season.