Isaac Chamberlain has sparred world champions such as Anthony Joshua, Deontay Wilder and Oleksandr Usyk, and now pursues his own title shot as he enters his prime
Isaac Chamberlain has learned from the very best along his boxing journey so far.
The 27-year-old cruiserweight contender went on the road in the early stages of his career to pick up experience in the gym with top champions.
First, as a young amateur, Chamberlain spent time in the gym with Anthony Joshua.
Just 19 at the time, the cruiserweight was able to give good rounds to the Olympic super-heavyweight gold medallist, who would of course go on to become two-time unified heavyweight world champion.
A year later, Chamberlain flew to Alabama, USA and sparred with Deontay Wilder.
Wilder at the time was preparing for a career-defining moment - his first world title fight against Bermane Stiverne.
Chamberlain too was working towards an important milestone as he used the experience to get ready for his professional debut.
“At the time I was 20. It was just amazing," Chamberlain recalled.
"I remember in the hotel room just after we landed. They said, 'Guys, just so you know, Deontay really wants this world heavyweight title.'
"They were like, 'Deontay really wants to win this world title so he's going to go really hard. If you want to go, now is the chance.'
“For me, now I was treating the sparring sessions if I was preparing for a fight. I was the first person in and I did well.
"Some of the sparring partners were trying to get a bit tasty and he would ice them out. I was thinking to myself, 'What the f***?'
"The second time we were there in sparring they said they were only going to use me that day. I think it was because I done better than all the sparring partners.
"I remember he did one thing that was completely different, I left myself open after throwing a jab and he threw a right uppercut. Everyone was surprised I was still standing.
"He hit me that hard I thought I was back in London!
"He's a really cool guy, he would speak with me after and tell me what I should work on. He was a great person to spar with.”
The work benefitted both men as Wilder defeated Stiverne to win the WBC title and Chamberlain emerged victorious on his debut two weeks later.
The Brit's career progressed to the point where he was a cruiserweight prospect catching the eye of the division's big names.
On two occasions, most recently in 2018, Oleksandr Usyk recruited Chamberlain for sparring in Ukraine.
Usyk was cruiserweight king at the time and went on to become undisputed champion in the division, before moving up and now being unified heavyweight champion.
"I wasn't really surprised," Chamberlain said of Usyk's win over Joshua, "I know how good he is.
"He's a sensational boxer. I've been in two camps with him. It's the subtle things that he does.
"The way he sets up attacks, feinting all the time, lead hand all the time. He's using his boxing brain a lot. He's very, very good at what he does.
"I did very, very well against him. They sang my praises, they said that I would definitely be coming back.
"I used to ask Usyk for advice all the time after the spars, but obviously when I would spar a bit better, he would stop giving me advice."
While Usyk continued to win, the same could not be said for Chamberlain.
In early 2018, he lost his unbeaten record in a scrappy fight with Lawrence Okolie.
At the time the pair were both young contenders, though Okolie has since proven himself as he now holds the WBO cruiserweight world title.
Chamberlain spent almost two years out of the ring between 2018 and 2020, but is now on the comeback trail as he enters his prime.
At 27, Chamberlain has returned with three confidence-building victories against lower level opposition.
On Friday night, live on Channel 5, he begins to step back up in levels with a fight against Dilan Prasovic.
The Montenegrin is familiar to UK fight fans as his last bout came as mandatory challenger facing Okolie for his WBO title in September.
It ended in KO defeat for him, ending his unbeaten record.
Chamberlain is now 13-1, while Prasovic is 15-1. Both only having lost to the WBO world champion Okolie.
An IBF 'international' belt is on the line, and this trinket could help push the winner up their rankings and towards an eventual shot at IBF champion Mairis Briedis.
"That's the plan," said Chamberlain. "He has the IBF and the Ring Magazine [titles]. I want to go straight for No 1.
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"He's getting old, but he's the best out of everyone, so I want to challenge myself against the best in the world. That's what we're going towards."
Isaac Chamberlain vs Dilan Prasovic will be free to watch on Channel 5 on Friday night, with their live coverage starting from 10.30pm. To stream, download the My5 app on you mobile, tablet or PC.