LAS VEGAS >> Robert Whittaker won the UFC interim middleweight title tonight, surging in the late rounds to earn a unanimous decision over Yoel Romero at UFC 213.

Whittaker (20-4) recovered from a hyperextended knee in the first round with a strong striking performance, peppering Romero (12-2) with punches and kicks over the final three rounds. The Australian won his eighth consecutive fight, earning the victory 48-47 on all three judges’ scorecards at T-Mobile Arena.

“It’s a moment I’ve always dreamed of,” Whittaker said. “My knee was definitely hurt. I injured it in camp, and Romero’s kick set it back weeks. I know that Romero will capitalize on any weakness he sees, so I had to play it off. That’s just what champions are made of.”

The main event of the UFC’s traditional July showcase was canceled earlier in the day when bantamweight champion Amanda Nunes was hospitalized. She was scratched from her second title defense against Valentina Shevchenko, who criticized the champion’s preparation for the bout.

Alistair Overeem beat Fabricio Werdum by narrow majority decision in the third career meeting of two veteran heavyweights. Former lightweight champion Anthony Pettis also returned to the division with a unanimous decision victory over Jim Miller in the final show of International Fight Week, the annual mixed martial arts celebration in the UFC’s hometown.

Whittaker took advantage of his bout’s promotion to the main event by claiming the belt in front of a pay-per-view audience. He earned the chance to fight for the full 185-pound title held for the past year by Michael Bisping, who is injured.

Bisping stepped into the cage afterward and congratulated Whittaker in his own irascible style.

“The fact that you’re standing there with a belt on makes me sick,” Bisping said, throwing his own belt on the canvas. “Take that belt. Fight for it.”

The 40-year-old Romero was gracious after his eight-fight winning streak ended, praising his opponent.

Bisping watched UFC 213 next to UFC President Dana White, his championship belt in front of him.

Romero’s aggression kept Whittaker on the defensive for much of the first two rounds, but Whittaker landed several impressive strikes. Whittaker increased his striking output while Romero sat back in the third and fourth, with Whittaker also defending Romero’s takedowns adroitly.

Romero was cut on his left eyebrow and the right side of his scalp, while Whittaker had a bloody nose and mouth in the final round, which was fought largely on the feet. Romero slipped onto his back with 90 seconds left, and Whittaker jumped on top to rain down blows.

Whittaker will get the chance to remove the interim designation from his belt when Bisping returns from injury, although it might not happen this year. The middleweight division has been in limbo ever since Bisping shockingly beat champion Luke Rockhold last summer and then fought old rival Dan Henderson instead of Romero, Whittaker or another top contender.

For the third straight year, the UFC had to change the main event of its annual July show in Las Vegas at short notice. Last year, Jon Jones was sidelined by a violation of the promotion’s anti-doping policy three days before his bout against Daniel Cormier at UFC 200.

Shevchenko still showed up at T-Mobile Arena after being denied her long-awaited title shot when Nunes fell ill in the hours before their bout, which will be a rematch of Nunes’ narrow win over Shevchenko in March 2016.

Shevchenko was furious with Nunes, claiming the champion’s drastic weight cut was responsible for her illness. She also echoed UFC President Dana White’s statement that Nunes was medically cleared to fight, but declined to go from the hospital to the cage.

“You can’t just say, ‘I don’t want to fight,’” Shevchenko said. “I couldn’t believe at the very last moment that this would happen to me. Of course I am upset. … I understand what she wanted. She wanted to cut (weight) in a very short time. You cannot do this. Our bodies need more time to recover.”

Shevchenko was greeted with loud cheers when she was shown on the arena’s video boards before the main event.

Overeem (43-15) and Werdum (21-7-1) finished a trilogy of fights between two of the most accomplished mixed martial artists of their generation. Werdum won their first meeting in the Pride promotion in 2006, and Overeem won their Strikeforce heavyweight rematch in 2011.

Overeem was slightly better during the first two rounds, which were fought tactically between smart veterans. Werdum then floored Overeem with a knee to the head early in the third and controlled the rest of the round, but Overeem apparently won the first two rounds on all three judges’ scorecards.

Pettis (20-6) returned to form in his return to 155 pounds, dominating the veteran Miller with flair and force. Pettis lost his title belt in March 2015 to start a 1-4 skid that included a two-fight stint at featherweight, but he looked sharp while carving up Miller (28-10), who bled copiously.

Before the pay-per-view portion of the card, heavyweight Travis Browne of Oahu took his fourth consecutive loss in a second-round submission to 40-year-old Russian grappler Aleksei Oleinik.

Browne (18-7-1), Ronda Rousey’s fiancé, lost for the sixth time in his last eight fights despite dropping Oleinik with punches in the first round.