David Haye feels he will have to train as hard as he ever has done in preparation for his clash with Manuel Charr - but insists he is not concerned about ring rust, despite having been out of action for almost a year.
The bout at Manchester Arena on June 29 will see former WBA heavyweight champion Haye fighting for the first time since his grudge match victory over fellow Briton Dereck Chisora in London in July 2012.
Charr, 28, has been in action on three occasions since then, suffering a controversial defeat at the hands of WBC champion Vitali Klitschko before bouncing back with two victories to take his record to 23 wins with just one defeat.
Haye (26-2), who had come out of retirement to fight Chisora, has no doubt he has his work cut out getting in shape for this contest, but has emphasised that he will be ready for Charr.
Speaking about Charr at a press conference attended by both fighters, Haye said: "He is very strong and durable and he has got a lot of heart.
"When I fought John Ruiz here, he had a lot of heart, he kept coming and it was a great, entertaining fight.
"This guy is a lot younger - he is 28 years of age, and I am going to have to train as hard as I have ever trained because anything less than perfect preparation will leave me with a hard night's work, which is not want I want.
"I want to go out there and do what I do best and knock somebody out.
"I am going to do whatever it takes to make that happen."
Asked if he was worried at all that he might be rusty from his time out of action, the 32-year-old told Press Association Sport: "No - I don't believe in rustiness.
"I believe that as long as your training goes well and your sparring is good, you should be able to perform on fight night. June 29 is the date and I'm looking at peaking on June 29.
"As long as sparring is competitive and I have nice young, fast guys to spar with, I don't believe there will be an issue."
Haye, who it was confirmed this week has agreed a "long-term relationship" with Eddie Hearn's Matchroom Sport, is looking to fight on a regular basis and is on a mission to become world heavyweight champion once more.
All the division's recognised world belts are held by the Klitschkos at the moment - Vitali's younger brother Wladimir is in possession of the WBA, IBF and WBO crowns - and with there being little sign of progress in negotiations between the Ukrainian siblings' camp and Haye's, the Londoner hopes to force the issue by putting himself in position to be mandatory challenger.
That process begins with the bout against Charr, who has been calling Haye out in an effort to land the fight.
The atmosphere between the two men was respectful today, though, with Haye suggesting he did not regard Charr's fourth-round stoppage loss due to a cut against Vitali Klitschko in September as legitimate.
Certainly that was the view of Charr, who said this afternoon: "I did not lose to Klitschko. He stole the fight.
"I was in my corner, he took me to the other corner and it was Klitschko's doctor who stopped the fight. This is not boxing - this is mafia boxing for me."
Charr went on to hail Haye - whose previous fight before Chisora was a loss to Wladimir Klitschko in 2011 - as the division's best fighter,
He said: "Vitali Klitschko says every time that he wants David Haye, but he is afraid of David Haye, who for me, is the number one heavyweight.
"I respect him, he is a great fighter."
Lebanon-born Charr, who resides in Germany and has Syrian heritage, added: "After this fight, I will give a lot of money for peace in Syria - to help the children, the wives, the people there.
"I am not about politics - I only fight for their freedom. I will give my best, because I don't fight for me, I fight for this country."Tags: David Haye , Manuel Charr , Haye-Charr , Haye vs. Charr