Derrek Lee homered twice and Ryan Dempster earned his third straight win as the Chicago Cubs topped the rival St. Louis Cardinals 9-7 on Sunday.

Marlon Byrd added two hits and Koyie Hill drove in a pair during a six-run fourth inning for the Cubs, who have won just seven of their last 18 games but have taken four of six from the rival Cardinals during that span.

Lee has been the subject of some criticism this season as his on-base and slugging percentages have fallen to career-low levels, but he showed his old form against the Cardinals. The first baseman homered in each of the first two games of the series and was at it again Sunday, hitting solo shots in the first and third innings to give Chicago the early lead before leaving in the fifth with back stiffness.

The Cubs broke it open in the fourth as Kyle Lohse (1-5) allowed the first five batters of the inning to reach before being removed. Hill, Dempster, Kosuke Fukudome and Byrd each drove in runs in the frame.

Lohse, who was making his first start since May 22 due to a right forearm strain, was charged with seven runs on six hits in three-plus innings.

Dempster (11-8) lasted 6 2/3 innings, allowing two runs and five hits while striking out six and walking two. He has three of Chicago’s four wins this month

The Cardinals made a game of it with a five-run eruption in the ninth inning, but Carlos Marmol snuffed out the rally for his 21st save.