Strikeforce lightweight champion Josh Thomson and interim champ Gilbert Melendez will unify their titles when they rematch in the main event of Strikeforce: Evolution on December 19 in San Jose, California.

Thomson defeated Melendez by unanimous decision last June to win the title, and the pair were set to meet in April and August but injuries have postponed the bout.

Thomson (16-2), who went 2-1 in a stint with the UFC that ended in 2004, has won eight-straight since losing to Clay Guida in his Strikeforce debut in early-2006, including wins over Duane Ludwig, Nam Phan, and Melendez. “The Punk” defeated Ashe Bowman in non-title action last September, but has yet to defend the title after a broken leg forced him to postpone his rematch with Melendez

Melendez (16-2) has won back-to-back fights since losing to Thomson last summer, winning the interim title with a second-round knockout of Rodrigo Damm in April before defending the belt and avenging his only other carer loss with a third-round TKO of Mitsuhiro Ishida in August.

“Evolution” also features the return of Cung Le against Scott Smith as well as Matt Lindland vs. Ronaldo “Jacare” Souza and Muhammed “King Mo” Lawal vs. Mike Whitehead.

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Pictured: Josh Thomson and Gilbert Melendez

Tags: gilbert melendez, Josh Thomson, Mike Whitehead, Muhammed Lawal