Shaun Marcum cruised through eight innings and Rickie Weeks drove in a pair as the Milwaukee Brewers trimmed their magic number to three with a 5-1 victory over the host Chicago Cubs on Tuesday.

Corey Hart, Nyjer Morgan and Ryan Braun each added RBIs for the Brewers, who own a 5 1/2-game lead over the St. Louis Cardinals in the National League Central. The Cardinals defeated the New York Mets 11-6 on Tuesday.

Marcum (13-7) bounced back from a pair of rough starts by striking out seven and not walking a batter in matching his longest outing of the season. The veteran righthander threw 68 of his 97 pitches for strikes.

Milwaukee did most of its damage in the third off Randy Wells, getting four consecutive one-out hits to plate three runs and driving a fourth across when Weeks followed Prince Fielder’s groundout with an infield single to third.

Starlin Castro’s home run in the sixth extended his streak of reaching base to 33 consecutive games. It marks the longest streak for Chicago since Jerome Walton reached in 43 straight in 1989.

Castro also has 197 hits, three shy of becoming the youngest Cub to reach 200.