PHOENIX -- Pitcher Kevin Brown was put on the 15-day disabled list by the New York Yankees on Tuesday because of a strained lower back.
The move was made retroactive to June 10, a day after Brown was forced to leave a start against Colorado after two innings. Outfielder Bubba Crosby was recalled from Triple-A Columbus.
The Yankees have the best record in the major leagues, but the health and depth of their rotation has been their top concern. Mike Mussina left his start Friday night against San Diego after three innings when he felt tightness in his right groin.
Jose Contreras was to start Tuesday night in Arizona and Tanyon Sturtze was to pitch Wednesday night against the Diamondbacks.
Brown, 39, is 7-1 with a 4.13 ERA in 13 starts during his first season with the Yankees.
The right-hander had an MRI exam, CT scan and X-rays last Thursday, a day after injuring himself. He was initially listed as day-to-day by the Yankees.
A six-time All-Star who earned his 200th career victory earlier this season, Brown has been beset by back problems.
He had surgery to repair a disc in 2002, and this marked his seventh time on the DL in six seasons.
After leaving his last start, Brown said he felt as if a "steel rod" was in his back.
Yankees manager Joe Torre recently said Brown has been having problems with his back since the start of the season and that it was important to "get it straightened out for Kevin's psyche."
Brown was traded to New York in the offseason in a deal that sent Jeff Weaver to Los Angeles.
Crosby has played 17 games for the Yankees and also 17 games for Columbus. He batted .240 with two home runs and seven RBIs with New York.