A bad case of the flu and an injury sustained in training will keep Buddy Roberts (12-3 MMA, 1-1 UFC) out of UFC on FOX 6, sources close to the fighter today told MMAjunkie.com (www.mmajunkie.com).

Roberts was slated to meet Michael Kuiper (12-1 MMA, 1-1 UFC) on the event’s FX-televised preliminary card, which follows prelims on Facebook and a four-fight main card on FOX.

UFC on FOX 6 takes place Jan. 26 at United Center in Chicago.

UFC officials could not be reached to confirm Roberts’ status, but additional sources close to the promotion said the organization is currently seeking a replacement opponent.

After an unspectacular decision over Caio Magalhaes at UFC on FX 3, Roberts accepted a short-notice fight at UFC 150 against onetime middleweight title contender Yushin Okami. He was defeated by second-round TKO, which snapped a six-fight win streak.

Roberts’ originally scheduled octagon debut was ill-fated, as well, with opponent Sean Loeffler bowing out of a fight at UFC on FUEL TV 1 due to an ankle injury suffered during warm-ups.

Kuiper, meanwhile, hopes to build a win streak after a second-round TKO of Jared Hamman at UFC 150, which reversed a decision loss to Rafael Natal in his debut at UFC 143.

For more on UFC on FOX 6, stay tuned to the UFC Rumors section of the site.