A Pakistani man living in Greece wraps a tennis ball in electrical tape before a tape-ball cricket game in a park in the Agioi Anargyroi suburb in Athens, Greece, June 23, 2019. Picture taken June 23, 2019. REUTERS/Alkis Konstantinidis 

Czech Republic's tennis player Petra Kvitova poses for a picture with her coaches during a news conference, after she was injured on Tuesday when she fought off an intruder in her home, damaging all the fingers on her playing hand, in Prague, Czech Republic December 23, 2016. REUTERS/David W Cerny 

Czech Republic's tennis player Petra Kvitova speaks during a news conference, after she was injured on Tuesday when she fought off an intruder in her home, damaging all the fingers on her playing hand, in Prague, Czech Republic December 23, 2016. REUTERS/David W Cerny 

Czech Republic's tennis player Petra Kvitova speaks during a news conference, after she was injured on Tuesday when she fought off an intruder in her home, damaging all the fingers on her playing hand, in Prague, Czech Republic December 23, 2016. REUTERS/David W Cerny 

Czech Republic's tennis player Petra Kvitova speaks during a news conference, after she was injured on Tuesday when she fought off an intruder in her home, damaging all the fingers on her playing hand, in Prague, Czech Republic December 23, 2016. REUTERS/David W Cerny 

Czech Republic's tennis player Petra Kvitova leaves after a news conference, after she was injured on Tuesday when she fought off an intruder in her home, damaging all the fingers on her playing hand, in Prague, Czech Republic December 23, 2016. REUTERS/David W Cerny 

Czech Republic's tennis player Petra Kvitova reacts during a news conference after she was injured on Tuesday when she fought off an intruder in her home, damaging all the fingers on her playing hand, in Prague, Czech Republic December 23, 2016. REUTERS/David W Cerny 

Czech Republic's tennis player Petra Kvitova speaks during a news conference, after she was injured on Tuesday when she fought off an intruder in her home, damaging all the fingers on her playing hand, in Prague, Czech Republic December 23, 2016. REUTERS/David W Cerny 

Czech Republic's tennis player Petra Kvitova speaks during a news conference, after she was injured on Tuesday when she fought off an intruder in her home, damaging all the fingers on her playing hand, in Prague, Czech Republic December 23, 2016. REUTERS/David W Cerny 

Czech Republic's tennis player Petra Kvitova speaks during a news conference, after she was injured on Tuesday when she fought off an intruder in her home, damaging all the fingers on her playing hand, in Prague, Czech Republic December 23, 2016. REUTERS/David W Cerny 

Football Soccer Britain - Everton v Manchester United - Premier League - Goodison Park - 4/12/16 Children play tennis in the streets outside the stadium before the match Action Images via Reuters / Carl Recine Livepic EDITORIAL USE ONLY. No use with unauthorized audio, video, data, fixture lists, club/league logos or "live" services. Online in-match use limited to 45 images, no video emulation. No use in betting, games or single club/league/player publications. Please contact your account representative for further details 

Juan Martin del Potro of Argentina's Davis Cup tennis team, holds a trophy after the team's arrival in Buenos Aires, Argentina, November 29, 2016. REUTERS/Agustin Marcarian 

Juan Martin del Potro of Argentina's Davis Cup tennis team, holds a trophy next to captain Daniel Orsanic upon their arrival in Buenos Aires, Argentina, November 29, 2016. REUTERS/Agustin Marcarian 

Juan Martin del Potro of Argentina's Davis Cup tennis team, gives thumbs up after the team's arrival in Buenos Aires, Argentina, November 29, 2016. REUTERS/Agustin Marcarian 

Juan Martin del Potro of Argentina's Davis Cup tennis team, kisses a trophy after the team's arrival in Buenos Aires, Argentina, November 29, 2016. REUTERS/Agustin Marcarian 

Members of the Argentina's Davis Cup tennis team hold up trophies after arriving in Buenos Aires, Argentina, November 29, 2016. REUTERS/Agustin Marcarian 

Juan Martin del Potro and captain Daniel Orsanic of the Argentina's Davis Cup tennis team attend a news conference upon their arrival in Buenos Aires, Argentina, November 29, 2016. REUTERS/Agustin Marcarian 

Tennis - Croatia v Argentina - Davis Cup Final - Arena Zagreb, Croatia - 27/11/16 Argentina's Juan Martin del Potro reacts after his victory against Croatia's Marin Cilic. REUTERS/Marko Djurica 

Tennis - Croatia v Argentina - Davis Cup Final - Arena Zagreb, Croatia - 27/11/16 Argentina's Juan Martin del Potro reacts after his victory against Croatia's Marin Cilic. REUTERS/Marko Djurica 

Tennis - Croatia v Argentina - Davis Cup Final - Arena Zagreb, Croatia - 27/11/16 Argentina's Juan Martin del Potro reacts after his victory against Croatia's Marin Cilic. REUTERS/Marko Djurica 

Tennis - Croatia v Argentina - Davis Cup Final - Arena Zagreb, Croatia - 27/11/16 Argentina's Juan Martin del Potro in action against Croatia's Marin Cilic. REUTERS/Marko Djurica 

Tennis - Croatia v Argentina - Davis Cup Final - Arena Zagreb, Croatia - 27/11/16 Argentina's Juan Martin del Potro reacts after his victory against Croatia's Marin Cilic. REUTERS/Marko Djurica 

Tennis - Croatia v Argentina - Davis Cup Final - Arena Zagreb, Croatia - 27/11/16 Argentina's Juan Martin del Potro reacts after his victory against Croatia's Marin Cilic. REUTERS/Marko Djurica 

Tennis - Croatia v Argentina - Davis Cup Final - Arena Zagreb, Croatia - 27/11/16 Argentina's Juan Martin del Potro reacts after his victory against Croatia's Marin Cilic. REUTERS/Marko Djurica 

Tennis - Croatia v Argentina - Davis Cup Final - Arena Zagreb, Croatia - 27/11/16 Argentina's Juan Martin del Potro reacts after his victory against Croatia's Marin Cilic. REUTERS/Marko Djurica 

Tennis - Croatia v Argentina - Davis Cup Final - Arena Zagreb, Croatia - 27/11/16 Argentina's Juan Martin del Potro reacts after his victory against Croatia's Marin Cilic. REUTERS/Marko Djurica 

Tennis - Croatia v Argentina - Davis Cup Final - Arena Zagreb, Croatia - 27/11/16 Argentina's Juan Martin del Potro reacts after his victory against Croatia's Marin Cilic. REUTERS/Marko Djurica 

Tennis - Croatia v Argentina - Davis Cup Final - Arena Zagreb, Croatia - 27/11/16 Argentina's Juan Martin del Potro reacts after his victory against Croatia's Marin Cilic. REUTERS/Marko Djurica 

Tennis - Croatia v Argentina - Davis Cup Final - Arena Zagreb, Croatia - 27/11/16 Argentina's Juan Martin del Potro reacts after his victory against Croatia's Marin Cilic. REUTERS/Marko Djurica 

Tennis - Croatia v Argentina - Davis Cup Final - Arena Zagreb, Croatia - 27/11/16 Argentina's Juan Martin del Potro in action against Croatia's Marin Cilic. REUTERS/Marko Djurica 

Tennis - Croatia v Argentina - Davis Cup Final - Arena Zagreb, Croatia - 27/11/16 Argentina's Juan Martin del Potro reacts after his victory against Croatia's Marin Cilic. REUTERS/Marko Djurica 

Tennis - Croatia v Argentina - Davis Cup Final - Arena Zagreb, Croatia - 27/11/16 Argentina's Juan Martin del Potro reacts after his victory against Croatia's Marin Cilic. REUTERS/Marko Djurica 

Tennis - Croatia v Argentina - Davis Cup Final - Arena Zagreb, Croatia - 27/11/16 Argentina's Juan Martin del Potro reacts after his victory against Croatia's Marin Cilic. REUTERS/Marko Djurica 

Tennis - Croatia v Argentina - Davis Cup Final - Arena Zagreb, Croatia - 27/11/16 Argentina's Juan Martin del Potro reacts after his victory against Croatia's Marin Cilic. REUTERS/Marko Djurica 

Tennis - Croatia v Argentina - Davis Cup Final - Arena Zagreb, Croatia - 27/11/16 Argentina's Juan Martin del Potro reacts after his victory against Croatia's Marin Cilic. REUTERS/Marko Djurica 

Tennis - Croatia v Argentina - Davis Cup Final - Arena Zagreb, Croatia - 27/11/16 Argentina's Juan Martin del Potro reacts after his victory against Croatia's Marin Cilic. REUTERS/Marko Djurica 

Tennis - Croatia v Argentina - Davis Cup Final - Arena Zagreb, Croatia - 27/11/16 Argentina's Juan Martin del Potro reacts after his victory against Croatia's Marin Cilic. REUTERS/Marko Djurica 

Tennis - Croatia v Argentina - Davis Cup Final - Arena Zagreb, Croatia - 27/11/16 Argentina's Juan Martin del Potro in action against Croatia's Marin Cilic. REUTERS/Marko Djurica 

Tennis - Croatia v Argentina - Davis Cup Final - Arena Zagreb, Croatia - 27/11/16 Argentina's Juan Martin del Potro reacts after his victory against Croatia's Marin Cilic. REUTERS/Marko Djurica 

Tennis - Croatia v Argentina - Davis Cup Final - Arena Zagreb, Croatia - 27/11/16 Argentina's Juan Martin del Potro reacts after his victory against Croatia's Marin Cilic. REUTERS/Marko Djurica 

Tennis - Croatia v Argentina - Davis Cup Final - Arena Zagreb, Croatia - 27/11/16 Argentina's Juan Martin del Potro reacts after his victory against Croatia's Marin Cilic. REUTERS/Marko Djurica 

Former tennis player Boris Becker poses for photographers at the world premiere of the film "I am Bolt" in London, Britain November 28, 2016. REUTERS/Neil Hall 

Tennis - Croatia v Argentina - Davis Cup Final - Arena Zagreb, Croatia - 27/11/16 Argentina's Federico Delbonis (C) and Juan Martin del Potro (R) react after winning the final of the Davis Cup as the Cup breaks. REUTERS/Antonio Bronic 

Tennis - Croatia v Argentina - Davis Cup Final - Arena Zagreb, Croatia - 27/11/16 Argentina's Federico Delbonis (C) and Juan Martin del Potro (R) react after winning the final of the Davis Cup as the Cup breaks. REUTERS/Antonio Bronic 

Tennis - Croatia v Argentina - Davis Cup Final - Arena Zagreb, Croatia - 27/11/16 Argentina's Federico Delbonis (C) and Juan Martin del Potro (R) react after winning the final of the Davis Cup as the Cup breaks. REUTERS/Antonio Bronic 

Tennis - Croatia v Argentina - Davis Cup Final - Arena Zagreb, Croatia - 27/11/16 Argentina's Federico Delbonis (C) and Juan Martin del Potro (R) react after winning the final of the Davis Cup as the Cup breaks. REUTERS/Antonio Bronic 

Tennis - Croatia v Argentina - Davis Cup Final - Arena Zagreb, Croatia - 27/11/16 Argentina's Federico Delbonis (C) and Juan Martin del Potro (R) react after winning the final of the Davis Cup as the Cup breaks. REUTERS/Antonio Bronic 

Tennis - Croatia v Argentina - Davis Cup Final - Arena Zagreb, Croatia - 27/11/16 Argentina's Federico Delbonis (C) and Juan Martin del Potro (R) react after winning the final of the Davis Cup as the Cup breaks. REUTERS/Antonio Bronic 

Tennis - Croatia v Argentina - Davis Cup Final - Arena Zagreb, Croatia - 27/11/16 Argentina's Federico Delbonis (C) and Juan Martin del Potro (R) react after winning the final of the Davis Cup as the Cup breaks. REUTERS/Antonio Bronic 

Tennis - Croatia v Argentina - Davis Cup Final - Arena Zagreb, Croatia - 27/11/16 Argentina's Juan Martin del Potro and Federico Delbonis react after winning the final of the Davis Cup. REUTERS/Marko Djurica 

Tennis - Croatia v Argentina - Davis Cup Final - Arena Zagreb, Croatia - 27/11/16 Argentina's Juan Martin del Potro and Federico Delbonis react after winning the final of the Davis Cup. REUTERS/Marko Djurica 

Tennis - Croatia v Argentina - Davis Cup Final - Arena Zagreb, Croatia - 27/11/16 Argentina's Juan Martin del Potro reacts after winning the final of the Davis Cup. REUTERS/Marko Djurica 

Tennis - Croatia v Argentina - Davis Cup Final - Arena Zagreb, Croatia - 27/11/16 Argentina's Leonardo Mayer, Guido Pella, Federico Delbonis, Juan Martin del Potro and Daniel Orsanic pose with the trophy during the victory ceremony. REUTERS/Marko Djurica 

Tennis - Croatia v Argentina - Davis Cup Final - Arena Zagreb, Croatia - 27/11/16 Argentina's Leonardo Mayer, Guido Pella, Federico Delbonis, Juan Martin del Potro and Daniel Orsanic react during the victory ceremony. REUTERS/Marko Djurica 

Tennis - Croatia v Argentina - Davis Cup Final - Arena Zagreb, Croatia - 27/11/16 Argentina's Leonardo Mayer, Guido Pella, Federico Delbonis, Juan Martin del Potro and Daniel Orsanic react during the victory ceremony. REUTERS/Marko Djurica 

Tennis - Croatia v Argentina - Davis Cup Final - Arena Zagreb, Croatia - 27/11/16 Argentina's Leonardo Mayer, Guido Pella, Federico Delbonis, Juan Martin del Potro and Daniel Orsanic pose with the trophy during the victory ceremony. REUTERS/Marko Djurica 

Tennis - Croatia v Argentina - Davis Cup Final - Arena Zagreb, Croatia - 27/11/16 Team Argentina poses with the trophy during the victory ceremony. REUTERS/Marko Djurica 

Tennis - Croatia v Argentina - Davis Cup Final - Arena Zagreb, Croatia - 27/11/16 Argentina's Juan Martin del Potro reacts after winning the final of the Davis Cup. REUTERS/Marko Djurica 

Tennis - Croatia v Argentina - Davis Cup Final - Arena Zagreb, Croatia - 27/11/16 Argentina's Juan Martin del Potro reacts after winning the final of the Davis Cup. REUTERS/Marko Djurica 

Tennis - Croatia v Argentina - Davis Cup Final - Arena Zagreb, Croatia - 27/11/16 Argentina's Leonardo Mayer, Guido Pella, Federico Delbonis, Juan Martin del Potro and Daniel Orsanic react during the victory ceremony. REUTERS/Marko Djurica TPX IMAGES OF THE DAY