China's Wang Qiang has sent 23-time grand slam champion Serena Williams crashing out in the third round of the Australian Open with a stunning straight-sets triumph.
The No.27 seed Wang, who beat Ashleigh Barty at last year's US Open, ousted the eighth-seeded American 6-4 6-7 (2-7) 7-5 in a match lasting two hours and 41 minutes.
The defeat means Williams, 38, remains one title behind Margaret Court on the all-time list of women's major winners.
Wang was on the verge of what would have been a straight-sets victory when she served for the match at 5-3 in the second set, only for Williams to secure her only break on Friday.
The seven-times Melbourne Park champion went on to dominate the tiebreaker.
But Wang held her nerve in a tense final set, securing the crucial break in the 12th and final game with her third match point.
"My team always believed I could do it," said Wang, who won only one game in her previous encounter with Williams in the quarter-finals at last year's US Open.
"After last year I did really hard work on and off the court."
Wang said she had no plans to celebrate Chinese New Year on Saturday, preferring instead to rest up and prepare for her fourth-round encounter with Ons Jabeur.
The Tunisian sent former world No.1 Caroline Wozniacki into retirement by beating the Dane 7-5 3-6 7-5.
In other matches, seventh seed Petra Kvitova from the Czech Republic belted No.25 seed Ekaterina Alexandrova from Russia 6-1 6-2.