Former Grand Slam tennis champion Dominic Thiem has made a shock switch to football.The 32-year-old retired from tennis in 2024, but he’s back in sport and has joined an eighth-tier side.Thiem achieved a moment of glory in 2020 with victory at the US OpenGetty Images - GettyAccording to reports, he has joined amateur club Badener AC.They are based in Thiem’s homeland of Austria, and it means he’s back on grass even if it is for an entirely different sport.Thiem officially registered with the Austrian FA earlier in July, meaning he is eligible to play for Badener.The former US Open winner is believed to have had a friend on the team, which has opened the door.But despite his reputation, he has been told that he must earn his place in the team.Thiem will also be present at the upcoming UEFA Super Cup between Paris Saint-Germain and Aston Villa.He has been announced as one of the ambassadors for the match, which is set to take place in Austria at Red Bull Salzburg’s ground on August 12, and it will be live on talkSPORT.Speaking about his ambassadorial role, he said: “Football has always been an important part of my life, whether I’m playing myself, watching in the stadium or cheering as a fan.“That’s why I’m even more excited to be part of the UEFA Super Cup 2026 as its official ambassador for Austria!“Can’t wait for this one!”Thiem has walked away from tennis, but he’s still claimed a Grand Slam and not many people can say thatGettyThiem’s retirementThiem is the only man in the Open Era to win a Grand Slam final from two sets down.He was on the brink of being beaten by Alexander Zverev in straight sets, only to rally and claim the match 2-6, 4-6, 6-4, 6-3, 7-6 (6).He also made it to three other Grand Slam finals across a glittering career that saw him win tens of millions in prize money.And his defeats in Grand Slam finals had no shame attached as he lost two French Open finals to the ‘King of Clay’ Rafael Nadal and an Australian Open to Novak Djokovic.He still won 17 career titles and when he announced his retirement, legends of the game all paid their respects.Roger Federer said: “You were always a super guy, also off the court.“Always fair. Your friendship was important on the Tour. We always got on well, and it was great for me.“All the best with the future, and huge congratulations on your unbelievable career, Dominic. I am sure we will see each other soon, but for now, have a great evening.”Thiem used the heartbreaking defeats to go on and achieve gloryDjokovic also praised Thiem.He said: “Thank you very much for all that you have given to all of us, but particularly tennis.“I’m glad that you have the opportunity to say goodbye in Vienna. One last dance.“I wish you a great tournament, with all your family members present, and celebrate it, because you deserve it my friend. All the best.”