Strikeforce lightweight champion Josh Thomson and interim champion Gilbert Melendez will look to unify the belts in a rematch on the Strikeforce: Evolution card on Dec. 19 in San Jose, Calif.

The fight has been rumored for quite some time, but the website of Melendez's Cesar Gracie camp has finally confirmed the bout. The rematch has already been twice promoted and canceled both times this year due to Thomson's ankle and leg injuries.

When the two enter the cage on Dec. 19, it will be a year and a half since Melendez (16-2) lost the title to Thomson (16-2) and Thomson's first title defense. Thomson fought once more in September, stopping Ashe Bowman in a non-title affair.

Following the title loss to Thomson, Melendez gained the interim title in his next fight in April 2009 over Rodrigo Damm and defended the belt in August while avenging a previous loss against Mitsuhiro Ishida.