Chicago has given up on trying to turn the 29-year old into a late-inning setup man. Zambrano was moved to the bullpen to help stabilize it in April.
"The reason we did it was because we needed him in the bullpen," Cubs pitching coach Larry Rothschild said. "Hopefully, and it looked like the last three or four times out, he got much more aggressive and more animated delivery-wise and let the ball go with a little better sense of purpose. Hopefully that carries over."
Zambrano will replace left-hander Tom Gorzelanny, who will move to the bullpen. Zambrano is 1-3 with a 6.12 ERA, and just 1-2 with a 7.45 ERA in four starts.
"I'm looking forward to seeing Zambrano," Cubs manager Lou Piniella said. "One of the keys for us going forward is Zambrano pitching well out of the rotation. He could give us a big boost there. But I look forward to seeing Zambrano, and he was throwing the ball very well in the bullpen the last four or five, six times he threw the ball. Let's hope that he can run off a nice little streak for us."
Zambrano appeared in the first two games of last weekend's series against the Cardinals. He worked a scoreless inning in Friday's 7-1 loss and two-thirds of a scoreless inning in Saturday's 5-0 victory. The Cubs feel he is sufficiently stretched out for Wednesday's start.
"I think he's good for 80 pitches," Rothschild said. "We'll see. Really, it's going to be delivery-wise how strong he looks, and if it looks like he's tired, then we have to make a decision. But he should be fine for 75 or 80 pitches, and on a good day maybe more."
Cubs general manager Jim Hendry is on the road swing with the team and will be watching Zambrano's start closely.
"I don't know if it was a wake-up call," Hendry said. "When a guy has that much experience in the big leagues, it's not necessarily a wake-up call. Hopefully it will be something that he turns into a positive, which could happen. He's been throwing the ball very well the last 10 days in a relief role. His simulated game the other day was real good. I'm hoping he'll be real hungry and see the other guys are certainly carrying their weight in the rotation. Hopefully it will be a good thing, obviously the break from not having the wear and tear and the innings at this point might help him."
George Von Benko is a contributor to MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.