Gael Monfils of France returns the ball to Lucas Pouille of France during their first round match at the Australian Open Grand Slam tennis tournament at Melbourne Park in Melbourne, Australia, 20 January 2015. EPA/JULIAN SMITH AUSTRALIA AND NEW ZEALAND OUT

Lleyton Hewitt of Australia returns the ball to Ze Zhang of China during their first round match at Rod Laver Arena during the Australian Open Grand Slam tennis tournament at Melbourne Park in Melbourne, Australia, 20 January 2015. EPA/DAVID CROSLING AUSTRALIA AND NEW ZEALAND OUT

Serena Williams of the USA returns the ball to Alison Van Uytvanck of Belgium during their first round match at the Australian Open Grand Slam tennis tournament at Melbourne Park, Melbourne, 20 January 2015. EPA/JULIAN SMITH AUSTRALIA AND NEW ZEALAND OUT

Vasek Pospisil of Canada celebrates after beating Sam Querrey of the USA in their first round match at Hisense Arena during the Australian Open Grand Slam tennis tournament at Melbourne Park in Melbourne, Australia, 20 January 2015. EPA/LUKAS COCH AUSTRALIA AND NEW ZEALAND OUT

Venus Williams of the USA serves to Maria-Teresa Toro-Flor of Spain during their first round match on Hisense Arena during the Australian Open Grand Slam tennis tournament at Melbourne Park, Melbourne, Australia, 20 January 2015. EPA/LUKAS COCH AUSTRALIA AND NEW ZEALAND OUT

Novak Djokovic of Serbia during his first round match against Aljaz Bedene of Slovenia at the Australian Open Grand Slam tennis tournament in Melbourne, Australia, 20 January 2015. The Australian Open tennis tournament goes from 19 January until 01 February 2015. EPA/Barbara Walton