After being recalled from Iowa before Wednesday's game, Maine pitched against the Philadelphia Phillies and was charged with three runs without recording an out.
"Maine could have thrown today, he didn't throw many pitches (Wednesday). He just has to go down and get more command," manager Dale Sveum said. "It's just getting new guys in to see what happens. (Parker) has been doing a nice job down there. He has a swing-and-miss slider and hopefully that continues here."
The 16th-round pick in the 2006 draft, Parker will be making his first major league appearance. The 26-year old has pitched in each of the last four seasons at Iowa, posting a 2.08 ERA over 13 outings with five saves.
Although Parker was being used as a closer down at Iowa, Rafael Dolis will still handle the closing duties for the Cubs, Sveum said.
"I liked (Parker) in spring training just because the plane of his fastball and he has an above-average slider," Sveum said. "That's one thing we need right now is somebody to be able to go through right-handers with a slider. He has velocity. It's a guy who has done a nice job and you have to start rewarding guys who are doing a nice job."