Chicago Cubs' Starlin Castro, left, celebrates with manager Lou Piniella after hitting a two-run home run against the St. Louis Cardinals during the third inning of a baseball game Saturday, July 24, 2010, in Chicago.(AP Photo/Nam Y. Huh) By Nam Y. Huh
St. Louis Cardinals' Ryan Ludwick watches teammate Matt Holliday play against the Chicago Cubs during the ninth inning of a baseball game Saturday, July 24, 2010, in Chicago. The Cubs won 6-5.(AP Photo/Nam Y. Huh) By Nam Y. Huh
Chicago Cubs' Starlin Castro hits a two-run home run against the St. Louis Cardinals during the third inning of a baseball game, Saturday, July 24, 2010, in Chicago.(AP Photo/Nam Y. Huh) By Nam Y. Huh
St. Louis Cardinals' Brendan Ryan, right, scores on Tyler Greene's two-run single as Chicago Cubs catcher Geovany Soto applies a late tag during the second inning of a baseball game Saturday, July 24, 2010, in Chicago.(AP Photo/Nam Y. Huh) By Nam Y. Huh
Chicago Cubs center fielder Marlon Byrd makes a leaping catch on a fly ball hit by St. Louis Cardinals' Yadier Molina during the second inning of a baseball game, Saturday, July 24, 2010, in Chicago.(AP Photo/Nam Y. Huh) By Nam Y. Huh
CHICAGO (AP) -- Rookies Tyler Colvin and Starlin Castro homered Saturday, completing a successful week at the top of Chicago's order and helping the Cubs to a 6-5 victory over the St. Louis Cardinals.
The Cardinals finally scored after being shut out the previous two days but still followed an eight-game winning streak with their third straight loss.
Since Cubs manager Lou Piniella decided last Sunday to put his two youngest position players atop the batting order, Colvin and Castro have combined to hit .385 with 13 runs and 11 RBIs.
One of the majors' lowest-scoring teams, Chicago has averaged 7.2 runs in the six games since the move, winning four times.
Colvin led off with a homer for the second straight day, the first Cubs player to do so since Alfonso Soriano in May 2008. The 24-year-old outfielder leads all rookies with 15 home runs.
After the Cardinals went up 2-1 on Tyler Greene's two-run second-inning single -- snapping their 21-inning scoreless streak -- Colvin drew a one-out walk in the third and scored when Castro homered on Blake Hawksworth's next pitch to put the Cubs ahead to stay.
Castro, a 20-year shortstop, also doubled and singled. He is batting .489 with eight runs and eight RBIs in his last 11 games.
Tom Gorzelanny (6-5), in Chicago's rotation only because Carlos Zambrano was suspended after a June 25 dugout altercation with teammates, has won his last four starts. He allowed three runs on seven hits and three walks in six innings.
Aaron Miles and Jon Jay opened the seventh with singles off reliever James Russell. Andrew Cashner came on to get Albert Pujols to hit a sacrifice fly to deep center, making it 6-4. Jay was thrown out stealing and Matt Holliday grounded out to end the threat.
Cashner gave up an unearned run in the eighth due to second baseman Ryan Theriot's error, but with two on and nobody out he got Randy Winn to fly out and Greene to ground into a double play. Carlos Marmol pitched a hitless ninth for his 18th save.
Hawksworth (4-6) left after allowing fifth-inning singles to Castro and Aramis Ramirez. Mitchell Boggs then walked Marlon Byrd and threw a wild pitch that let Castro score. Catcher Yadier Molina misfired while trying to throw out Castro and Ramirez came home on the error to put the Cubs up 6-3.
Byrd added an RBI double for the Cubs, who on Sunday will go for their first sweep of the Cardinals in four years.
NOTES: St. Louis RF Ryan Ludwick came off the DL (left calf) and went 1 for 3 with a walk. ... On the one-year anniversary of his Cardinals debut, Holliday extended his hitting streak to 10 games but was retired on a soft liner to end the game. ... Colvin's 15 HRs are the most by a Cubs left-handed-hitting rookie since Mel Hall had 17 in 1983. ... The Cubs agreed to terms with second-round draft pick Reggie Golden, an outfielder from Wetumpka, Ala.
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