Francis Tiafoe, USA, in action during his astonishing win over number one seed Andrey Rublev, Russia, in the Junior Boys' Singles Quarterfinals. Tiafoe blew a 6-1, 5-1 lead to win the third set 6-4 in sweltering heat during the US Open Tennis Tournament, Flushing, New York, USA. 5th September 2014. Photo Tim Clayton