Anthony Joshua believes Tyson Fury is the opponent who could cause him the most problems and has claimed he could knock Deontay Wilder out with one shot.
With WBC heavyweight champion Wilder, WBO belt holder Joseph Parker and former champion Fury all keen to fight him, the stage is set for a blockbuster 2018 for WBA and IBF king Joshua.
All four men are undefeated but, while bouts with Wilder and Parker may soon be in the offing, the path to a fight with Fury is more difficult.
Fury has not fought since dethroning Wladimir Klitschko for the WBA, IBF and WBO belts back in November 2015. He does not have a boxing licence and is still awaiting the resumption of a UK Anti-Doping hearing after allegations were made against him.
Joshua's fellow Briton has also struggled to stay in shape in his absence, but the 28-year-old still feels Fury has the skillset and the mindset to trouble him more than Wilder and Parker.
Asked who would be the most difficult opponent of the three, Joshua, speaking courtesy of Jumeirah Hotels & Resorts/Sports Tonight, said: "Fury. He's just awkward, tall and I think he's a bit of a nutjob to be honest with you.
I think he's just got a bit of a screw loose. Any man with a screw loose... they just have a little something that you can't put your finger on. So with Fury it would be tricky to figure him out.
"I think I know what I have to do with Wilder. Parker, I don't disregard him but... I'd smack Parker around the ring, no problem.
"Wilder, I'd knock Wilder out. It would take a bit of time but I'd definitely knock him out. Parker would take a bit more of a pasting but I'd get to him. Wilder, I'd knock him out with one shot. Not like I'd go in there and bang but when I catch Wilder, I'd definitely knock him out.
"And Fury would be a real breakdown job, a real gruesome type fight. Kind of like that Klitschko fight - I'll go to hellfire and back to get the win."
Joshua was knocked down in his 11th-round win over Klitschko back in April, while Fury emerged relatively unscathed from his unanimous decision triumph against the now-retired Ukrainian.
However, Joshua said of Fury's performance: "Boxed 12 rounds and ran. I don't respect that.
"If I'm the King of Dubai in the olden days and a different empire comes to take my territory, you don't come and steal my treasure - that's what Fury done I think. He stole the boxing from Klitschko in the sense that he just boxed and moved - I know it's the art of boxing, but...
"I always said that you come to slay the King. You look him in his face and you take what's his. And that's what I think me and Klitschko done. We came together man to man and just went to war. And I think that's relit the division as well."