Anthony Joshua and Tyson Fury will contest their long-awaited all-British heavyweight fight at Cardiff’s Principality Stadium on 11 December.
The bout, more than a decade in the making, will be broadcast globally on Netflix.
BBC Sport understands the main event could take place in the early hours of Saturday morning in the UK, with organisers considering a late start to cater for audiences in the United States.
Joshua and Fury will come face-to-face at a news conference in London on Wednesday, 30 September, as the build-up begins to one of the most anticipated fights in British boxing history.
“I am inspiring a generation,” Joshua, 36, posted on Instagram.
The event is being promoted as a collaboration between Saudi boxing powerbroker Turki Alalshikh’s The Ring and UFC chief Dana White.
“Two of the best heavyweights of this generation, finally in the ring together,” Alalshikh said.
“This will be one of the biggest fights in boxing history. I am very happy to make this fight happen for the fans.”
The former two-time world champions had already signed contracts for the bout earlier this year, but the date and venue had yet to be confirmed.
London’s Wembley Stadium and New York’s Madison Square Garden were the frontrunners to stage the fight, but both presented issues before Cardiff recently emerged as an alternative.
Joshua had been pushing for the fight to take place in the UK and has got his wish.
“Forever indebted to the UK public for their support of Anthony Joshua. We couldn’t have got this over the line without you,” his promoter Eddie Hearn said.
The Principality Stadium has hosted late-night boxing before, including Joe Calzaghe’s fight with Mikkel Kessler in November 2007, which began at 01:00 GMT.
