Fifth seed Dominic Thiem has been knocked out of the Australian Open in the fourth round by world number 97 Tennys Sandgren.
The Austrian lost 6-2 4-6 7-6 (7-4) 6-7 (7-9) 6-3 in three hours 55 minutes.
Sandgren, 26, had never won a match at a Grand Slam before this event and is only the second man in the last 20 years to reach a quarter-final on his Melbourne debut.
The American will play Novak Djokovic or Hyeon Chung in the last eight.