Marlon Byrd laced a two-run single to cap a four-run sixth inning as the Cubs doubled up the Cardinals 6-3. Alfonso Soriano clubbed a two-run homer in the ninth to help Chicago avoid a three-game sweep. Ryan Dempster struck out six over six innings to improve to 8-and-8. Carlos Marmol nailed down his 20th save. Lance Berkman belted a three-run homer in the sixth for St. Louis. Jake Westbrook was perfect through five innings but imploded in the sixth. Westbrook allowed four runs on three hits and three walks to fall to 9-and-5. The Northsiders head to PNC Park this evening to kick off a four-game series against the Pittsburgh Pirates. Carlos Zambrano will be on the bump opposite Paul Maholm [[ muh-HALL-um ]] in tonight's opener.