Yesterday, UFC lightweight contender T.J. Grant (21-5 MMA, 8-3 UFC) announced via twitter that he is still not 100% and will not be able to compete against Anthony “Showtime” Pettis at this December’s UFC on FOX 9 event in Sacramento, California.

With Grant unable to compete, the UFC has given former Strikeforce lightweight champion, Josh Thomson, the opportunity to vie for the 155-pound strap.

The UFC’s change in plans was revealed on FOX Sports 1’s “FOX Sports Live,” shortly after Grant’s tweets.

Josh Thomson (20-5 MMA, 3-1 UFC) returned to the UFC in emphatic fashion this April, scoring a second-round TKO over former title challenger Nate Diaz at the UFC on FOX 7 event in San Jose, California.

Prior to his octagon return, Thomson went 9-3 while fighting under the Strikeforce banner, which saw him win and hold the promotions lightweight belt for a little over a year in 2008-2009.

Meanwhile, Anthony “Showtime” Pettis (17-2 MMA, 4-1 UFC) was most recently seen in action at UFC 164 in his hometown of Milwaukee, where he submitted Benson Henderson in the first-round to earn the UFC lightweight championship.

“Showtime” was given the opportunity to fight Benson Henderson at UFC 164 after T.J. Grant suffered a concussion in training, forcing the Canadian off the August card.

Before defeating “Smooth” for the second time in his career, Pettis had scored back-to-back finishes over Donald Cerrone and Joe Lauzon respectively.

UFC on FOX 9 takes place December 14 live from the Sleep Train Arena (formerly ARCO Arena) in Sacramento, California. Pettis vs. Thomson will serve as the events headliner which airs live on FOX.