Anthony Joshua will fight Alexander Povetkin at Wembley in September, promoter Eddie Hearn has confirmed.
IBF, WBA and WBO champion Joshua and Hearn had earlier announced dates for two fights at the national stadium in London, with bouts on September 22 this year and April 13, 2019.
And Povetkin, as expected, will provide the Briton's first opponent.
"I can't wait to get back in the ring, the end of March [the Joseph Parker fight] feels a long time ago now," said Joshua (21-0).
"Povetkin is a serious challenge that I will prepare meticulously for. He has serious pedigree and only a fool would underestimate what he brings to the table.
IT’S ON! @anthonyfjoshua will defend his WBA,IBF,WBA and IBO World heavyweight titles against Alexander Povetkin at @wembleystadium on September 22! New York press conf tomorrow and London on Wednesday pic.twitter.com/NDCn7EpgvX— Eddie Hearn (@EddieHearn) July 16, 2018
"Training hasn't stopped for me, but the next 10 weeks ahead will be intense, both mentally and physically.
"I will push myself to breaking point to make sure I am in peak condition for another huge night for British boxing at Wembley Stadium on September 22."
Povetkin (34-1) added: "The battle for the world title has always been my goal. I fought for the moment to face the strongest in the world and, on September 22, I get my opportunity.
"Anthony Joshua has four belts and I want them all. I'm glad that our fight will finally take place, the meeting of two Olympic champions in the ring is destined to be a breathtaking event."
Joshua had been ordered by the WBO to take the mandatory fight to defend his belt, as negotiations faltered with Deontay Wilder over a potential unification bout.
Wilder remains a possible opponent for April after Hearn confirmed last week that Joshua is ready to sign a contract.
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