is an Austrian professional tennis player. His career-high ATP ranking in singles is world No. 3, which he first achieved on 2 March 2020, and in doubles is No. 67, which he achieved on 7 October 2019. He is the second-highest ranked Austrian player in history, behind former world No. 1 Thomas Muster. He has won 17 ATP Tour singles titles, including one Grand Slam title at the 2020 US Open where he came back from two sets down to defeat German Alexander Zverev in the final. With the win, Thiem became the first male player born in the 1990s to claim a Grand Slam singles title, as well as the first Austrian to win a US Open singles title. He had previously reached three other Grand Slam finals, losing at the 2018 and 2019 French Open to Rafael Nadal, and at the 2020 Australian Open to Novak Djokovic. Thiem was also the runner-up of the 2019 ATP Finals, where he lost to Stefanos Tsitsipas.