St. Louis Cardinals starting pitcher Jake Westbrook sits in the dugout after giving up four runs to the Chicago Cubs. UPI/Bill Greenblatt

Cardinals starting pitcher Jake Westbrook retired the first 16 Chicago Cub batters he faced, but then unraveled by giving up four runs in the 6th inning as the Cardinals lost 6-3 Sunday night at Busch Stadium.

Westbrook falls to 9-5 after using just 44 pitches to get through the first five innings, but he allowed five straight Cubs to reach bases after two outs in the sixth as Chicago jumped to a 4-0 lead.

In the bottom of the sixth, the Cardinals battled back scoring three off Cubs’ starter Ryan Dempster (who only allowed two hits in the first five innings) on Lance Berkman’s three run homer. He leads the league with 28.

Alfonso Soriano hit a two run homer in the ninth off Kyle McClellan, who just went back to the bullpen after the Cardinals acquired starting pitcher Edwin Jackson.