An injury suffered in training has forced top welterweight contender Diego Sanchez (19-2 MMA, 7-2 UFC) out of a highly anticipated bout with Thiago Alves (15-3 MMA, 8-2 UFC) at “UFC 90: Silva vs. Cote.” With less than two weeks until the event, fellow top welterweight Josh Koscheck (11-2 MMA, 9-2 UFC) has stepped in to fill the void.

Fiveouncesofpain.com were the first to report the change, and MMAjunkie.com confirmed the news with sources close to the bout.

UFC 90, which features a main event between UFC middleweight champion Anderson Silva and Canadian slugger Patrick Cote, takes place at the Allstate Arena in Rosemont, Ill.

Sanchez suffered an injury to his ribs in training last week. A time table for his return has not been announced.

Koscheck had recently been tabbed for a main event bout with Yoshiyuki Yoshida at the UFC’s “Fight for the Troops” on Dec. 10. It is unknown at this time whether Koscheck will still participate in the December outing.

The bout between Sanchez and Alves was viewed as a No. 1 contender bout, determining who would meet the winner of a January welterweight title clash between Georges St. Pierre and B.J. Penn. Koscheck will now look to earn that position on short notice.