PITTSBURGH — No. 3 middleweight Luke Rockhold beat David Branch with a flurry of strikes in the second round of a showdown between ranked fighters Saturday night, re-establishing himself as a contender in the division.

Rockhold (16-3) took Branch to the ground in the second round and established top control, hammering blows on Branch's head and neck. Branch submitted 4:05 into the period.

The fight was Rockhold's first since losing the middleweight title to Michael Bisping last June. But after a 16-month layoff that included a knee injury, Rockhold again feels ready to challenge for the title.

"I'm coming for that belt," he said. "This is my fight."

Bisping is scheduled to fight George St. Pierre in November. St. Pierre will be returning from a nearly four-year retirement, while Bisping hasn't fought since October. Rockhold doesn't consider St. Pierre a legitimate contender for the title and said he'll stay ready to fight in November if the Canadian former champ backs out. He also said he'd consider fighting interim champion Robert Whittaker.

"He's the true champion right now," Rockhold said of Whittaker. "The man who fights the fights that count other than some poser up there running away with the belt."

Rockhold also said he's considered a future at light heavyweight, but won't make that move while Daniel Cormier remains champion in that division.

Branch (21-4) showed off his boxing prowess early, backing Rockhold up against the cage with an aggressive attack in the first round. That led the jiu-jitsu-trained Rockhold to take him to the ground.

"I wanted to work on the feet more, but he was just rushing forward so much into the clinch and just laying on me" Rockhold said. "I think anybody in this sport, once I get on top of them, they're not going to last long."

Branch, who entered the fight ranked ninth in the division, took his first defeat since May 25, 2012, breaking an 11-bout unbeaten streak.

"I'm right there, I've just got more work to do," Branch said. "I came to UFC to be the champion. ... I've come back from adversity before and I'm going to do it again."

In the co-main event, welterweight Mike Perry improved to 11-1 with a knockout via knee strike over Alex Reyes at 1:19 of the first round. Perry was originally scheduled to fight Thiago Alves, who backed out of the fight due to travel concerns related to Hurricane Irma. But Perry wasn't convinced that was the only concern.

"He ran from me," Perry said. "The kudos go to my opponent, who took the fight on three days' notice."

Kamaru Usman, the No. 13 welterweight, knocked out Sergio Moraes with a straight right hand to the jaw in the first round. After the victory, he declared himself to be "a problem" in that division and called out former lightweight champ Rafael dos Anjos, who recently moved up to welterweight.

Also at welterweight, former All-American wrestler Gregor Gillespie grappled his way to a chokehold submission victory over Jason Gonzalez in the second round. The two stood up and battled to a bloody, non-stop stalemate in the first before Gillespie prevailed on the mat.

On the preliminary card, No. 14 middleweight Uriah Hall came back from an ugly first round to knock out No. 10 Krzysztof Jotko. Hall was knocked down and bloodied by Jotko in the first, stopped him with an overhand right in the second round.