"We'll stick with Wells for right now," Cubs manager Dale Sveum said. "Something could change, but right now Wells will pitch on Tuesday."
The 29-year-old right-hander struggled in his first opportunity, surrendering five hits, four walks and three earned runs over 3 2/3 innings in a 7-0 loss to the White Sox on Wednesday.
In 25 2/3 innings this season, Wells has walked 20 and struck out only 11.
"The walks have killed him, especially the non-competitive ones," Sveum said. "He's got to get the ball over the strike zone. We have to get that turned around. You have to make them put the ball in play."