Nathan Cleverly has been gearing up for the biggest fight of his life by letting loose on his mate James DeGale.
The boxing buddies have been sparring together ahead of the biggest fights of their careers in Sky Box Office HD's double header on May 21.
DeGale takes on bitter rival George Groves while Cleverly challenges WBO light-heavyweight champion Juergen Braehmer for his world crown.
The Welshman admits it is his toughest test to date but says that's why he has enlisted the help of his Frank Warren stablemate. The pair have sparred before in the Welshman's gym but this time he has made the trip to Jim McDonnell's headquarters in Essex.
"It's important to have that element of competitiveness in sparring," he told Sky Sports News HD.
"Sometimes we mix it up between nice movement and letting the big shots go. It's important to adapt and to get used to taking those big shots.
"We get on very well. We obviously understand what it takes to become a champ and we've got great respect for each other.
"I rate him very highly - that's the reason I came down to London. I was looking for a good southpaw to spar with and the best opponent was James DeGale. He's obviously preparing for a massive fight on the same night, so it made sense."
Cleverly knows he will have to produce the best performance of his 21-fight career to take the title away from Braehmer.
The champion boasts an impressive amateur record - including a first-round knockout of Ricky Hatton - and is a class above anyone he has faced so far.
He has though had problems out of the ring and in February was handed a 16-month prison sentence for attacking two people in separate incidents in 2008.
He is appealing the decision but will not have boxed 13 months by the time he climbs into the ring at the 02 Arena and although Cleverly is wary of his class, he says the time is right to make the step up.
"Juergen Braehmer is a real world-class fighter. He's a massive puncher, he's had 38 fights, 36 wins with 29 knockouts. He holds wins over Ricky Hatton and Carl Froch as an amateur and was amateur world champion.
"He's got a great pedigree but I'm thriving on the challenge.
"It's probably the most important night of my life and the most important fight of my life, there's no doubt about that.
"I've got to go in there and rip the belt from the champion and it's a real 50-50 fight. But I really fancy the job."