(AP) - Jay Bruce hit his first career grand slam and Joey Votto added a two-run homer in an all-rookie power display that sent the Cincinnati Reds to a 10-2 victory over the division-leading Chicago Cubs.

The Cubs' losing streak reached a season-high six games against a team already eliminated from the race.

Ted Lilly (13-9) gave up five runs, including Votto's 18th homer. The left-hander has started four times against the Reds this season and lost all four.

Bruce hit his 16th homer off Jon Lieber for a 9-0 lead in the fourth inning as Bronson Arroyo (14-10) won his fourth straight start, allowing one run in 6 1-3 innings of a game that kicked off the Cubs' longest road trip of the season.

The start of the game was delayed 17 minutes by rain, which fell intermittently during the early innings.

Despite their losing streak, the Cubs have won 85 games _ most in the National League _ and have been in first place since May 11.

But September has been disastrous. Ace Carlos Zambrano got an injection in his sore pitching shoulder yesterday and will miss at least one start. Right-hander Rich Harden also will miss a start because of a bothersome arm.

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