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Al Behrman, Associated Press
Cincinnati Reds' Joey Votto hits a double to drive in a run in the third inning of a baseball game against the St. Louis Cardinals, Sunday, July 15, 2012 in Cincinnati.

CINCINNATI — Reds first baseman Joey Votto will have surgery to repair torn cartilage in his left knee, leaving the NL Central leaders without their best hitter for the next three to four weeks.

The 2010 National League MVP hurt the knee while sliding into third base on June 29 in San Francisco, but has continued playing. Votto started for the National League in the All-Star game last Tuesday.

A medical exam on Monday evening detected the tear. Votto will have arthroscopic surgery on Tuesday.

"It is in my best interest and in the best interest of the team to do it now so that I can be healthy during the last two months of the pennant race," Votto said in a statement.

Votto is batting .342 with 14 homers and 49 RBIs. He leads the National League in doubles, walks, on-base percentage and extra-base hits.

He went hitless in his first two games back from the All-Star game, then had a single and an RBI double during a 4-2 win over St. Louis on Sunday night that moved the Reds into sole possession of first place.

The Reds didn't immediately make a move to replace him on the roster.

Cincinnati has been in first place for 45 days because of its pitching and the NL's top defense. The Reds have used only five starters, a modern franchise record this deep into the season, and their bullpen is the best in the league.

The offense has struggled, ranking in the middle of the league. The loss of Votto costs the team its most consistent hitter.

Manager Dusty Baker gave Votto a day off on Monday because of his busy All-Star week, providing a little time to rest.

"His leg's a little sore, too, so it's two-fold," Baker said before Votto had the knee exam. "Sometimes you don't like it (a day off), you don't want to do it, but you have to do it."

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