While admitting he has lived his dream as a professional footballer, Sordell revealed he has experienced an "ugly side to the game", including racism and bullying.

He wrote in a statement on Twitter: "The 6-year-old me would never even have dreamed of what the 28-year-old me has achieved in this game.

"I managed to experience some of the greatest highs on offer: playing for England, for Team GB in the Olympics and in the biggest league in the world, in the form of the Premier League.

"In over 300 matches, for the nine clubs and three national teams I played for, I scored goals that I dreamed about as a young boy in the park.

"I'll be honest though, the ugly side of the game that many of us are exposed to, has had a hugely detrimental effect on my mental health. I witnessed, and was on the receiving end of racism on several occasions and have seen an incredible amount of bullying, manipulation and verbal abuse to an extent which for many leaves a dirt stain on this industry.

"The combination of these aspects, allow me to move on from being a professional football player, knowing that I will be a happier man, and also be able to love the game again, in a way that I haven't for many years."

Sordell has also had spells at Burnley, Colchester and Coventry since leaving Bolton and spent the second half of last season on loan at Northampton.

The striker admits his mental health is something he has struggled with throughout his career and is determined to help others.

"My mental health has been severely impacted throughout my career, therefore I feel it's the right time to move forward in my life," Sordell told the Burton website.

"I have always been eager to help people who have had similar problems in their lives and going forward I'd like to be able to make a difference in football when it comes to mental wellbeing."

Burton manager Nigel Clough said: "We want to thank Marvin for the contribution he has made during his time at Burton Albion.

"We totally understand his decision and he leaves with the very best wishes of everyone at the club.

"We are sure Marvin has a massive amount to contribute in helping people with their mental wellbeing and we look forward to seeing all that he achieves in the future."