A welterweight bout has been added to UFC on FOX 15 in April as Kenny Robertson will meet George Sullivan on the preliminary card. 
UFC officials announced the fight booking on late Wednesday evening.
UFC on FOX 15 will come from the Prudential Center in Newark, New Jersey on April 18 and will be headlined by a middleweight bout as Lyoto Machida meets Luke Rockhold.
Robertson (15-3) has won three fights in a row, including a performance of the night victory against Sultan Aliev at UFC on FOX 14. Since returning to the UFC, he has gone 4-2 and three of those wins have come by stoppage. Sullivan (16-3, 1NC) signed with the UFC at the beginning of 2014 and is currently on an eight fight winning streak. Two of those wins have come in the UFC and the last victory came in September against Igor Araujo.
The current UFC on FOX 15: Machida vs. Rockhold fight card is below.
Lyoto Machida (22-5) vs. Luke Rockhold (13-2)
Aljamain Sterling (10-0) vs. Takeya Mizugaki (20-8-2)
Jim Miller (24-5, 1NC) vs. Paul Felder (9-0)
Felice Herrig (10-5) vs. Paige VanZant (4-1)
Eddie Gordon (7-2) vs. Chris Dempsey (10-2)
Corey Anderson (4-0) vs. Gian Villante (12-5)
Nick Catone (10-4) vs. Vitor Miranda (10-4)
Kenny Robertson (15-3) vs. George Sullivan (16-3, 1NC)