There was a massive shock at the Australian Open on Saturday as fourth seed Alexander Zverev was knocked out by Chung Hyeon.
Zverev went into the tournament as one of the favourites to be crowned champion, but he could not advance past the third round as he lost in five sets to the inspired Korean.
The German got off to a good start as he took the lead following a 7-5 triumph in the first set.
Hyeon fought back to level in the second set, but it looked as if Zverev would prove to be too good as the 20-year-old took the third to build a 2-1 advantage.
But Hyeon, ranked 59th in the world rankings, took the fourth to force a last set decider, and he took advantage of his tiring opponent by taking the last 6-0 to secure a memorable victory.
That meant that Zverev's hopes of achieving the first Grand Slam triumph of his career ended in major disappointment once again.
The German has previously been tipped by many as a future major winner, but he is still yet to progress past the fourth round in a Grand Slam.
THE 41 SHOT RALLY
With the match barely two minutes old, Zverev and Hyeon produced a thrilling 41 shot rally which wowed the Australian crowd.
The momentum shifted a number of times during the rally as both players could not find a way past their opponent.
Towards the end of the rally both players were evidently tiring, and Hyeon looked as if he may have gone long as his backhand narrowly clipped the baseline.
But it was called in, and just a few shots later the rally was eventually ended when Zverev hit the net with a wild forehand.
HYEON'S REWARD FOR DEFEATING ZVEREV
That victory may prove to be the biggest of the 21-year-old's career, but he may face an even bigger challenge in the fourth round.
Hyeon will now face the winner of Novak Djokovic and Alberto Ramos-Vinloas, with the Serbian the heavy favourite to advance in that tie.
But regardless who the Korean faces, he will again go into the tie as the underdog.
Will he be able to pull off another massive upset and advance to his first Grand Slam quarter-final?
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