Former world heavyweight champion Wladimir Klitschko retired because “the fire wasn’t there any more”, says his long-term manager Bernd Boente.
Klitschko, 41, ended his 21-year professional career on Thursday, three months after losing to Briton Anthony Joshua in a thrilling bout at Wembley.
There had been reports the pair were close to agreeing a rematch.
“Wladimir has nothing to prove. He is one of the best heavyweights in the history of the sport,” Boente said.
Speaking to BBC Radio 5 live, he added: “He always said if I’m missing the motivation or health that I will retire.”
Boente said that, despite the decision, Ukrainian Klitschko still believed he could beat Joshua in that much-anticipated rematch, which many within the sport expected to take place in Las Vegas in November.
Boxing record website BoxRec – which charts the progress of fighters – had even placed a 11 November rematch on the records of both men.
“The final decision was yesterday,” added Boente. “We met in a restaurant, we had dinner and then Wladimir said: ‘I’ve listened to my stomach and my brain – and both tell me that this is it.’
“He said he’d had a fantastic career and didn’t want to overdo it and that this is the right point. I definitely think that is the right decision and I support it 100%.”