Sean Strickland pulled off a massive upset at UFC 328 in Newark, New Jersey, defeating previously undefeated Khamzat Chimaev by split decision to reclaim the UFC middleweight championship.

Strickland revealed after the fight that he suffered a grade one AC joint separation in his shoulder during a sparring session just days before the bout. The injury forced him to alter his pre-fight routine, fearing he could aggravate it.

Chimaev, a heavy favorite with a 16-0 UFC record, dominated the first round, taking Strickland down within 15 seconds. But Strickland found his rhythm in the second round, keeping the fight on his feet and landing strikes. The two warriors battled through five bloody rounds.

In a bizarre moment late in the fifth round, Chimaev pointed to the mat-a signal for a stand-up brawl. Strickland agreed, but when he put his hands up, Chimaev shot for a takedown. Despite the trick, Strickland held on for the victory.

After the decision was announced, Chimaev showed respect by placing the belt around Strickland's waist. The 35-year-old champion drew loud "U-S-A!" chants from the crowd throughout the night.