Light heavyweight champion Andre Ward has retired from boxing undefeated at the age of 33.

The American won a re-match with Sergey Kovalev by technical knockout in the eighth round in Las Vegas in June, having defeated the Russian in a unanimous points decision in November 2016 to unify the WBA, IBF and WBO belts. 

There had been talk of Ward fighting David Haye's recent conqueror Tony Bellew at cruiserweight or even jumping up the divisions to take on heavyweight champion Anthony Joshua.

However, the 33-year-old - considered one of the pound-for-pound best - will instead hang up his gloves.

In a statement released on his website and titled 'Mission Accomplished', Ward was candid about the reason for his decision to retire.

"I want to be clear – I am leaving because my body can no longer put up with the rigors of the sport and therefore my desire to fight is no longer there," he wrote.

"If I cannot give my family, my team, and the fans everything that I have, then I should no longer be fighting."

A light heavyweight gold medal winner at the 2004 Olympic Games in Athens, Ward calls time on his undefeated career with a record of 32 victories, 16 by knockout.

He previously held the unified WBA and WBC super middleweight titles following landmark victories over Mikkel Kessler, Carl Froch and Chad Dawson. 

"To the sport of boxing – I love you," his statement read.

"You've been by my side since I was 10 years old. You've taught me so much. You've humbled me. You've promoted me. I've sacrificed a lot for you, but you've given me more than I ever thought possible. 

"You gave me a platform, made me a champion and helped me provide for my family. I am forever grateful to you. You and I will always be synonymous, connected at the hip. Thank you for all the wonderful people I've come in contact with because of you. I've made friends for life. 

"As I walk away from the sport of boxing today, I leave at the top of your glorious mountain, which was always my vision and my dream. I did it. We did it.

"From the bottom of my heart, thank you to everyone who has played a part in my journey. You know who you are. I could not have done this without you... Above all, I give God the Glory, for allowing me to do what I've done, for as long as I have."