Former world heavyweight champion Wladimir Klitschko says he is bowing out from boxing to focus on a new career he has "been planning for some years".
The 41-year-old's retirement puts the plug in plans for a rematch with unified champion Anthony Joshua, who knocked out Klitschko in the 11th round of their bout at Wembley in April.
Klitschko, who reigned supreme over the heavyweight division for nine years between 2006 and 2015, is drawing the curtain on a career of 64 wins and five defeats — two of which came in his final two bouts against Joshua and fellow Briton Tyson Fury in November 2015.
He is now turning his attention to making a new career outside the ring as fruitful as his years within it.
"27 years ago I started my journey in sport and it was the best choice in a profession I could have ever made," said the Ukrainian.
"Because of this choice I've travelled the world, learned new languages, created businesses, built intellectual properties, helped people in need, became a scientist, entrepreneur, motivator, hotelier, trainer, investor and much else.
"I was and am still capable of doing all this because of the global appeal of sport and boxing, because of my talent and, most importantly, because of you, my loyal fans.
"At some point in our lives we need to or just want to switch our careers and get ready for the next chapter and fresh challenges. Obviously, I am not an exception.
"Now, it's my turn. I'm obviously doing this with the greatest respect to the new challenges but also with tremendous excitement, passion and dedication, expecting and hoping that my next career, which I've already been planning and working on for some years will be at least as successful as my previous one - if not even more successful."
What next for Anthony Joshua?
Joshua and promoter Eddie Hearn had hoped to use a rematch with Klitschko as the 27-year-old's first fight in the US, with November 11 in Las Vegas pencilled in as a location and date by the Matchroom boss.
The pair's blockbuster bout at Wembley was the most lucrative fight in British boxing history and brought Joshua to America's attention thanks to broadcasts on HBO and Showtime.
Bulgarian Kubrat Pulev is now the mandatory challenger for Joshua's IBF belt.
Joshua must fight the 36-year-old, whose only defeat in 26 fights came against Klitschko in 2014, before 2 December or risk being stripped of his IBF belt.
American Deontay Wilder, the WBC world heavyweight champion, would provide Joshua with an opportunity to stage a box office hit in the US.
Matchroom stable mates Luis Ortiz, the WBA mandatory challenger, or Dillian Whyte could perhaps be staged relatively quickly and risk-free by Hearn.