The slimmed-down right-hander showed he may be ready to change that pattern in his season debut, and he'll take the mound again for Sunday's series finale against the visiting Chicago Cubs.Westbrook is 7-15 in April since 2005, with a 5.52 ERA -- nearly a run higher than his ERA in any other month during that span. He was 2-2 with a 6.53 ERA in April last season before finishing 12-9 with a 4.66 ERA, earning his most victories since 2006, when he won 15 games for Cleveland.Westbrook, who lost around 20 pounds in the offseason, got this campaign off to a much better start by yielding one unearned run and three hits over seven innings of Monday's 7-1 victory at Cincinnati."He's got some confidence going for him now," manager Mike Matheny told the Cardinals' official website.Westbrook will try to use that confidence to help St. Louis (6-3) stifle the Cubs' bats for a second straight day. Chicago (3-6) had totaled 17 runs and 23 hits in consecutive wins before Saturday's 5-1 loss.After receiving their World Series rings, the Cardinals limited their archrivals to six hits -- five singles and a double -- and scored all the runs they needed with four straight hits in the fourth inning. Yadier Molina singled in two of the four runs in that frame, and Jon Jay added a solo homer in the seventh to help St. Louis earn its eighth victory in its last 11 home meetings with the Cubs.Chicago will give the ball to left-hander Paul Maholm, who allowed six runs over four innings of a 7-4 loss to Milwaukee on Tuesday, his debut for the Cubs after spending his first seven major league seasons in Pittsburgh. He gave up five of those runs in the first inning."It was a bad inning. I didn't throw like I normally throw," Maholm said. "I don't know if it was my first game and I just tried to different things, but I didn't establish my sinker. I didn't do what I normally do."Despite spending his entire career in the NL Central, Maholm (0-1, 13.50) will be toeing the rubber in St. Louis for the first time since April 6, 2009.He's 1-1 with a 2.79 ERA in three lifetime starts at Busch Stadium, but 1/3 with a 5.27 ERA in his last seven overall matchups with the Cardinals.St. Louis slugger Matt Holliday is 3 for 24 in his career off Maholm, but two of those hits were homers.Westbrook gave up two runs over seven innings in his last start against the Cubs, a 6-2 win at Wrigley Field on Aug. 21. He had posted a 9.72 ERA while losing his previous two outings versus Chicago last season.Already expected to be without Lance Berkman (strained left calf), the Cardinals might also have to play again without David Freese, who is batting .406 with three homers and 11 RBIs. The World Series MVP is day to day after being scratched from Saturday's game because of irritation in one of the fingers of his right hand.