Strikeforce lightweight champion Josh "The Punk" Thomson has been forced out of his upcoming title fight against Gilbert Melendez with a broken ankle, as confirmed to MMAWeekly.com on Thursday.

Thomson was set to defend his 155-pound divisional belt for the first time, against the fighter he beat for the title last year, but the injury will sideline the California native for several months.

According to sources, Thomson had a clean break of the ankle, and the unfortunate timing will not only keep him out of the fight with Melendez, but out for an undetermined amount of time with the injury.

Melendez has been out of action since losing the title in June 2008, and was hopeful for a chance to regain the belt, but will have to hold on for a while longer to get a shot at Thomson.

There has been no word from Strikeforce officials at this time if they will replace Thomson and give Melendez a new opponent. The first Strikeforce show on Showtime will take place on April 11 in San Jose, Calif., with the main event pitting Frank Shamrock against Nick Diaz.

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