Dillian Whyte sealed a contract to take on WBC heavyweight champion Tyson Fury Just hours before the deadline.
Fury has confirmed the bout is set to take place on April 23 at Wembley Stadium.
33-year-old Whyte, had until 06:00 GMT on Tuesday to sign the contract, but he had spent the weekend and Monday ironing out the terms and final details of the deal.
Fury went on social media to taunt his opponent. He said “Dillian Whyte signed his contract for $8m, what a surprise”
Fury added: “The man’s signed for the biggest payday he’s going to get in his life.”
In a later video on Tuesday, he informed his followers that he would now be taking a break from social media as he trains for the match.
“I’m about to go off social media completely for the next eight and a half weeks,” he said.
“I’m going into training camp to give Dillian Whyte all the respect in the world he needs. I’ll never underestimate anyone in my life.
“Don’t phone me, call me, email me, text me or try to contact me in any way as I am out of bounds until May. I’ll be training away. Please respect my privacy and space. See you all at the press conference.”
As the WBC’s number-one-ranked contender, Whyte is the mandatory challenger to Fury’s WBC belt and has been waiting years for a chance at the world title.
Frank Warren’s Queensberry Promotions won the purse bidding in January with a $41 million (£30 million) bid, beating Whyte’s promoter Eddie Hearn, who was the only other bidder, after lengthy conversations between both parties came to naught.
33-year-old Fury, is now poised to get 80% of the prize, or roughly £20 million, with Whyte receiving the other 20%.