ROBBIE LAWLER vs MATT BROWN Watch FREE Live Stream Online UFC On Fox: PRELIMS, Full Fight Card

Tonight at 8:00 p.m. ET Robbie Lawler and Matt Brown will step inside the Octagon and battle for the No. 1 contender slot in the UFC welterweight division. Prior to that big showdown, there will be preliminary fights getting underway that can be watched by clicking this link. Fans can move on to the prelim matchups before the main card starts and find that action here. The fights will also air live on Fox.

Brown was unable to make weight for this fight, weighing in 1.5 pounds over the contracted 171-lb. limit, but after a discussion with the California State Athletic Commission he was able to avoid a financial penalty. He will also still be eligible for the No. 1 contender spot if he wins.

Lawler bounced back from a loss to Johny Hendricks for the interim title with a victory over Jake Ellenberger at UFC 173 in late May, and will step into the octagon with a 23-10 record that includes 19 knockouts.

"It's definitely exciting times to get to fight on FOX, a main card, a title-contender fight. It's huge, but I'm pretty relaxed. I don't worry too much about that. It's a big opportunity on a big stage and I'm excited," Lawler said.

"I'm not trying to go in there and mess around. He's a really good opponent. I'm not looking to go back-and-forth. I'm looking to dictate and dominate this fight, and that's what I train to do,"

Brown is 19-11 in his career with 12 knockouts; he also is a year older than Lawler, but he won't be intimidated when the opening bell sounds. He's on a seven-fight winning streak, a mark topped only by Chris Weidman (8) and Jon Jones (11), and has won 17 of his 19 bouts by knockout or submission.

Full Fight Card:

Robbie Lawler vs. Matt Brown

Anthony Johnson vs. Antonio Rogerio Nogueira

Clay Guida vs. Dennis Bermudez

Josh Thomson vs. Bobby Green

Undercard (FOX at 6 p.m. ET)

Jorge Masvidal vs. Daron Cruickshank

Kyle Kingsbury vs. Patrick Cummins

Hernani Perpetuo vs. Tim Means

Michael De La Torre vs. Brian Ortega

Undercard (UFC Fight Pass at 4 p.m. ET)

Akbarh Arreola vs. Tiago dos Santos