DUBAI, March 1, 2019  Stefanos Tsitsipas of Greece reacts during the singles quarterfinal match between Stefanos Tsitsipas of Greece and Hubert Hurkacz of Poland at the ATP Dubai Duty Free Tennis Championships 2019 in Dubai, the United Arab Emirates, Feb. 28, 2019. Stefanos Tsitsipas won 2-1 to proceed to the semifinals. (Credit Image: Â© Mahmoud Khaled/Xinhua via ZUMA Wire)