The long-discussed flyweight champ vs. bantamweight champ superfight now is official.

The UFC today announced the bout between bantamweight champion T.J. Dillashaw (16-3 MMA, 12-3 UFC) and flyweight titleholder Henry Cejudo (13-2 MMA, 7-2 UFC) for the UFC 233 main event. Dillashaw will move down 10 pounds to challenge for Cejudo’s 125-pound belt in an attempt to become the UFC’s latest simultaneous two-division champion.

UFC 233 takes place Jan. 26 at Honda Center in Anaheim, Calif. The main card will air on pay-per-view following prelims likely for ESPN+ and UFC Fight Pass.

Cejudo is a Los Angeles native. Dillashaw is from farther north in California, but now trains in Southern California, making it a home fight for both champions.

Dillashaw is No. 1 in the latest USA TODAY Sports/MMAjunkie MMA bantamweight rankings. Cejudo is No. 1 at flyweight. Dillashaw is the No. 8 pound-for-pound fighter in the world on that list, and Cejudo is not far behind at No. 11.

Discussions of a fight between the two champions started in August when each won title fights at UFC 227 at Staples Center in Los Angeles. Dillashaw defended his bantamweight belt in a rematch with Cody Garbrandt in the main event. He stopped the former champ with a first-round TKO. And Cejudo won a split decision against long-reigning flyweight champ Demetrious Johnson in the co-feature to win the belt in an upset. That fight was a rematch, as well.

But now that Johnson has left the UFC for ONE Championship, the prospect of a rematch between him and Cejudo is out the window completely if it ever was on the table to begin with. That opens the door for Dillashaw to move down to become the latest to attempt to hold two UFC titles simultaneously.

Currently, Daniel Cormier is the UFC’s heavyweight and light heavyweight champion – though the 205-pound title will be stripped from him when Jon Jones and Alexander Gustafsson fight for the belt in the UFC 232 main event. Previously, Conor McGregor was a simultaneous featherweight and lightweight champion. He eventually was stripped of both titles for failing to defend them.

The latest UFC 233 lineup now includes:

• Henry Cejudo vs. T.J. Dillashaw – for flyweight title
• Ben Askren vs. Robbie Lawler
• Islam Makhachev vs. Francisco Trinaldo
• Paul Felder vs. James Vick
• Yana Kunitskaya vs. Marion Reneau
• Joanne Calderwood vs. Ariane Lipski

For more on UFC 233, check out the UFC Rumors section of the site.