The 32-year-old American holds the only belt not owned by Joshua, and promoter Eddie Hearn is determined to see his man become the undisputed heavyweight champion of the world.
“You have to give the fans what they want and that is ultimately the Wilder fight,” he told talkSPORT.
“It has to happen in 2018 because the governing bodies put mandatory defences on you. You can’t defend all the belts at once and the only way you get around it is by having a unification fight.
“So if we don’t get it done in 2018, we may never get it done. Joshua wants to fight Wilder ASAP.”
And, courtesy of The Times, here’s how the two rivals compare.
Victory against Parker was the third stadium fight for Joshua in a year.
“I’ve got no issue fighting anyone,” the champion said. “If you look through my record from my 21 fights, there hasn’t been an issue with fighting anyone. There is no fear. There should be no hold-ups and [the Wilder] fight should be sooner rather than later.
“Does he need me more than I need him? Yes. Without being big-headed, that’s 100 per cent. He needs British boxing. He’s bigger here than he is in the States because of us.”
1. IBF (top right)
Won by beating Charles Martin in 2016 and Joshua fulfilled his mandatory commitments by beating Carlos Takam in October. An eliminator between Kubrat Pulev and Dominic Breazeale — who Joshua has already beaten — has been ordered to decide the next mandatory challenger. It would not be called until at least October.
2. WBO (top left)
Secured by beating Joseph Parker on Saturday. Parker’s last mandatory defence was against Hughie Fury in Manchester last September. It is not due until 18 months after that date. The No 1 contender is Alexander Povetkin, so it might be possible to fulfil two mandatory commitments in one fight.
3. IBO (bottom left)
A fringe title also held by Joshua. The vacant IBO belt was one of those at stake against Wladimir Klitschko last year, after it had become vacant when Tyson Fury was relieved of his licence in October 2016 due to medical issues and an anti-doping investigation. The IBO does not order mandatory challenges.
4. WBA (bottom right)
Joshua lifted the WBA’s ‘’Super’ title after knocking out Klitschko in the 11th round at Wembley Stadium. The next mandatory challenger is expected to be Povetkin, the Russian former WBA champion who knocked out David Price on Saturday, but that has not been ordered yet.
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