Three heavyweight world titles will be on the line when Joshua and Parker do battle on March 31.
The WBA (Super), IBF and WBO belts will all be claimed by the winner.
There’s also another belt in play – the IBO (International Boxing Organisation) belt, currently held by Joshua.
The winner is likely to face Wilder, in what would be the first heavyweight unification champion with all four Major heavyweight champion. But first, two the best the best heavyweights will face off tonight.