MLB Odds have the Cardinals as a -150 moneyline favorite, the Cubs as a +130 underdog, and the over/under total at 8.5.
The Cubs will give the ball to Ryan Dempster, who is 7-8 with a 4.98 ERA. The righthander last started on Tuesday July 26, going six innings in a 3-2 loss to the Milwaukee Brewers. The Cardinals will counter with righthander Jake Westbrook. He has a 4.86 ERA and is 9-4 this season. He last started Tuesday, going six innings in a 3-1 win over the Astros.
The teams have already met twice this season, with St. Louis winning the first series 2-1 from May 10 to 12 and sweeping the second June 3 to 5. The Cardinals won the opener of this series on Friday in a 9-2 rout, covering as a -135 home favorite. The score went over the over/under total of 7.5.
Chicago (42-64 SU) is in fourth place in the NL Central division, 15.5 games back of the first-place Milwaukee Brewers. The Cubs had lost four straight heading into the second game of the series Saturday. Chicago is 4-6 SU in its past 10 games.
St. Louis (56-50 SU) is second place in the division and is 1.5 games back of the Brewers. The Cardinals are 6-4 SU in their past 10 games.