A flyweight title rematch between Joshua Van and Alexandre Pantoja will headline UFC 331 in September, officials announced Thursday. The event takes place Sept. 19 at Crypto.com Arena in Los Angeles. Van (17-2) won the UFC’s 125-pound championship in a first-round TKO over Pantoja (30-6) in December, though the result was unsettled after Pantoja suffered a freak elbow injury in the opening seconds. Van has expressed interest in a rematch to solidify his status as champion, having defended the belt once against Tatsuro Taira in May.

The co-main event features a five-round lightweight showdown between Arman Tsarukyan and Mauricio Ruffy. Tsarukyan (23-3), widely regarded as the division’s top contender, returns after a November submission win over Dan Hooker. The 29-year-old, 10-2 in the UFC with a five-fight win streak, previously withdrew from a title fight against Islam Makhachev due to back spasms. Ruffy (14-2), ranked No. 7, is a rising prospect with four knockouts in five UFC victories.

Brett Okamoto, an ESPN combat sports reporter since 2010, covers the event. He has interviewed top fighters and produced the "Chuck and Tito" 30 for 30 film.

UFC 331 promises star power with Van’s rematch and Tsarukyan’s return, marking a pivotal night for the lightweight and flyweight divisions.