The former Wolfsburg and Hertha Berlin defender moved to the MLS in March 2012 on a free transfer after injury cut short his spell at the Volkswagen Arena.

During his eight years at Hertha Friedrich, 34,, made 231 appearances and also became a regular for Germany, making 82 appearances for his country.

When the club were relegated from the top division in 2011 he moved to Wolfsburg, but after one season and just 15 appearances, he was released and made the decision to move to America.

He made 23 appearances in his debut season with Chicago and was named defender of the year by the club.

However, the back injury that curtailed his Bundesliga career eventually ended his time in the MLS, with Friedrich having not made a single appearance for Fotios Klopas' team in 2013.

On Sunday he announced that he was retiring from the game.

"After much consideration and consultation with my doctors and physical therapists I have decided to finish my professional soccer career," a statement on his official website read. "The last couple of weeks and month I have been suffering from increasing back pain. 

"With two herniated discs in my lower back, I am no longer able to fulfill the demands of a professional soccer player.

"For this reason, I have asked the Chicago Fire to terminate my contract. I wish the 'Fire' and their fantastic fans all the best. My time in Chicago was awesome, I made new friends and will consider Chicago to be a second home. But now the time has come to take care of my body and start a new chapter in my life."