Serena Williams' illustrious tennis career has come to an end after she loses to Ajla Tomljanovic 7-5 6-7 (4-7) 6-1 in the third round of the US Open. The 23-time Grand Slam winner was on the brink of retirement in the second set when the pair went to a tie-break, but a resilient Williams — roared on by an electric crowd inside Arthur Ashe Stadium — produced some of her best tennis to force a decider. Ad However, it was Tomljanovic who showed incredible resolve to win the third set on her sixth match point and book her place in the fourth round for the first time in her career.