Kell Brook believes that Amir Khan has "messed about" during the build-up to their fight and is now sounding "negative" in his new training camp.
Brook and Khan's 17-year rivalry will finally be settled in Manchester on February 19, live on Sky Sports Box Office, in one of the best all-British fights available.
While Khan has been running in the snow in the Colorado mountains alongside his new trainer Brian 'BoMac' McIntyre and his former opponent Terence Crawford, Brook has been in the Fuerteventura sunshine.
Brook told Sky Sports that he senses weakness in Khan: "Amir is mentioning that he's got niggles. He's putting it out there that he's negative.
"I want to tell Khan: The fans have been waiting for years for this fight.
"I will turn up even if I've got two broken hands."
Khan had told Sky Sports last week: "We all have injuries, all sportsmen and women at the elite level. I've got pains and injuries but I have to overcome them."
Brook continued: "He messed about when we got contracts over the line.
"Now we've got a date, let's make this fight happen. I want him to turn up on February 19, the best he can be.
"The fans have been waiting too long. I've been waiting too long.
"I'm more than ready to show the world that I'm the best.
"After this fight, Amir will be a mere memory."
Both Khan and Brook have fallen short in world title challenges against undefeated pound-for-pound sensation Crawford, whose trainer McIntyre is now in Khan's corner.
"After seeing what Crawford did to Kell," McIntyre said, "I believe that Amir can do the same thing."
Brook hit back: "I don't believe so.
"Amir keeps banging on about his trainer and having world champions in his camp.
"Dominic Ingle, my trainer, has known me since I was teenager. He knows me inside-out. He knows when to push me, when not to push me, when I need a rest.
"Amir said he hasn't had a day off in a month.
"A rest is as good as a hard training session. The body needs to recover. His trainer has never worked with him - he doesn't know how to push Amir.
"We have no excuses."
Brook rejected Khan's accusation that he is "bitter", saying: "It's just talk. If he wants to believe it, let him carry on.
"He's in a fairy world. He loves the media. That's what he's about.
"I tie these gloves on, not for the flash of the cameras, but to become the world champion and the best in my sport."
Khan has been training at altitude in the US while Brook has been in the familiar territory of the Canary Islands, the scene of many of his training camps - cycling between the gym and his villa and recuperating by the swimming pool.
Brook warned: "I'm putting myself through hell.
"People will remember me by this fight. It took years for this grudge match to finally get here.
"The fans have been waiting for this fight for a long time."
BOXXER promoter Ben Shalom has revealed that Khan and Brook will be hit by a six-figure fine for every pound that they weigh above the contracted weight of 149lbs.
"I have always made weight," Brook insisted.
"I gave myself the opportunity to get away from Sheffield, away from the distractions, to take pressure away.
"I make the weight healthily. Everything is bang on track."
Sky Sports Boxing schedule
Sunday January 16 - Top Rank in New York
Joe Smith Jr vs Steve Geffrard - WBO light-heavyweight title
Sunday January 30 - Top Rank in Tulsa
Robson Conceicao vs Xavier Martinez - WBC super-featherweight title eliminator
Saturday February 5 (targeted) - BOXXER in Cardiff
Chris Eubank Jr vs Liam Williams
Claressa Shields vs Ema Kozin - IBF, WBA and WBC middleweight titles
Saturday February 19 - BOXXER in Manchester
Amir Khan vs Kell Brook
Frazer Clarke's pro debut
Saturday February 26 - BOXXER and Top Rank in Glasgow
Josh Taylor vs Jack Catterall - undisputed super-lightweight titles
Saturday March 5 - Top Rank in Fresno
Jose Ramirez vs Jose Pedraza