Well, Brad Tavares wasn't on the UFC 137 main card for long. Two days after it was annouced that the TUF 11 veteran's bout with newcomer Dustin Jacoby was going to be on pay-per-view, Tavares got hurt and had to pull out of the fight. He'll be replaced by a newcomer and the fight will be moved back down to the prelims. And a bantamweight fight that arguably should have been put there in the first place will get moved up. UFC.com has it:
With middleweight prospect Brad Tavares forced from his UFC 137 bout against newcomer Dustin Jacoby due to injury, another Octagon debutant will step in, as Clifford Starks will put his 7-0 record on the line against the 6-0 Jacoby.
Starks just competed on October 15th, defeating Artenas Young in the main event of Shark Fights 20. That's quite the turnaround time to make your UFC debut.