Rookies Starlin Castro and Tyler Colvin powered the Chicago Cubs to victory on Saturday.

Castro belted a two-run homer and Colvin added a solo shot as the Cubs posted their second straight victory over the St. Louis Cardinals with a 6-5 triumph on Saturday.

Castro also scored on a wild pitch in the fifth inning for Chicago (45-53).

Tom Gorzelanny (6-5) allowed three runs and seven hits in six innings to pick up the victory.

Two relievers bridged the gap to Carlos Marmol, who retired the side in the ninth - with a pair of strikeouts - to record his 18th save of the season.

Tyler Greene had a two-run single and Albert Pujols and Jon Jay had run-scoring sacrifice flies for St. Louis (54-44), which has dropped three in a row after winning eight consecutive games.

Blake Hawksworth permitted six runs and seven hits in 4 1/3 innings to take the loss.