CHICAGO (Ticker) -- San Diego Padres second baseman Bret Boone, among the most durable players in the game, today was placed on the 15-day disabled list with a bruised right knee.

The move, which is retroactive to August 27, marks the first time Boone has been on the disabled list since the opening week of the 1996 season. He had played in 131 straight games before resting the injury on August 21.

Boone had missed four of six games since and today the Padres decided to err on the side of caution. Boone has been solid in his first season with San Diego, hitting .251 with 19 homers and 74 RBI. The RBI total is the highest in club history by a second baseman.

Boone and first baseman Ryan Klesko were acquired from Atlanta for Reggie Sanders, Quilvio Veras and Wally Joyner during the offseason. He began his career with the Cincinnati Reds and is a third-generation major leaguer.

To fill Boone's roster spot, the Padres recalled infielder Kevin Nicholson from Class AAA Las Vegas. Nicholson hit .223 with a homer and eight RBI in 34 games for San Diego earlier this season.