
Andy Murray leaves the court after losing to Kevin Anderson during their men's singles fourth round match at the 2015 U.S. Open on September 7, 2015 in Queens, New York.

Murray often lost his composure during the tense encounter.

South Africa's Anderson returns a shot to Murray during their match on day eight of the U.S. Open. Anderson tallied 20 aces by the fourth set, at service speeds of 138mph.

Stan Wawrinka of Switzerland celebrates after defeating Donald Young of the United States during their fourth round match.

Young of the U.S. put up a valiant effort against world No. 5 Wawrinka before losing in four sets. Staff had mistakenly cleared Young's locker the day before the match.

Victoria Azarenka of Belarus celebrates after defeating Varvara Lepchenko of the U.S. 6-3 6-4 in their fourth round match.

No. 2 seed Simona Halep of Romania kicks the ball after losing a game to Sabine Lisicki of Germany during their fourth round match. After a heat break before the third set, Halep went on to win the grueling match to advance to the quarterfinals.

Temperatures over the past week at the U.S. Open have consistently touched above 90F (32C). Here Jack Sock of the U.S. receives assistance from trainer Hugo Gravil for heat exhaustion before withdrawing from his second round match against Ruben Bemelmans of Belgium.

Venus Williams and younger sister Serena Williams will meet in a quarterfinal showdown at the U.S. Open on Tuesday.