An ailing Novak Djokovic crashed out of the Australian Open in the fourth round as up and comer Hyeon Chung clinically took advantage of the six-time champion's elbow injury to win 7-6 (7-4) 7-5 7-6 (7-3).
The Serbian, who had also struggled with his hip in the third round, was on the back foot from the off and failed to claw back the first set before suffering further at the start of the second.
Djokovic's fighting spirit never wavered, but he could not shake off NextGen champion Chung, who was unrelenting en route to claiming the biggest scalp of his career.
Chung – the first Korean male or female to reach a grand slam quarter-final – had said prior to the match that he would "just be happy to share the court with Novak", but he was far from starstruck and an outstanding performance made him a deserved winner - albeit Djokovic, who missed six months before returning to play in Melbourne, was undoubtedly hindered by his injury.
The 21-year-old will now face another shock quarter-finalist in Tennys Sandgren on Wednesday.
Welcome to the big time Hyeon #Chung!— #AusOpen (@AustralianOpen) January 22, 2018
Our six-time champion Novak #Djokovic bows out of the #AusOpen d by the world No.58 in straight sets 7-6(4) 7-5 7-6(3) after 3hrs 21mins. pic.twitter.com/lETvt3JPJC
A series of unforced errors, including numerous double faults, allowed Chung to break Djokovic's serve twice and move 4-0 up in the first set, before the former world number one came roaring back.
Three successive games piled the pressure on Chung and errors crept into the youngster's play as he served for the set, but he battled through to the tie-break and recovered his momentum to take the set.
It was clear that Djokovic, wearing a protective sleeve on his right arm, was struggling with his elbow as he repeatedly failed to hold serve and he received treatment before the second set.
Chung held his nerve in a gruelling first game and broke the 14th seed en route to building a 3-0 lead.
As in the first set, Djokovic's fighting spirit came to the fore as he drew level, but Chung again showed great resolve and he moved two sets ahead when a stunning rally ended with the groaning 30-year-old finding the net.
A topsy-turvy third set followed, bringing the crowd to its feet as four of the first five service games were broken to leave the pair neck and neck.
Both players missed big opportunities to then take control of proceedings and a number of poorly telegraphed drop shots from the world number 58 ensured Djokovic remained in the match.
But Chung kicked off the tie-break with two superb points and, although again there was a strong response, he continued to confound Djokovic with some astounding returns to seal a huge win.
Chung bt Djokovic  7-6 (7-4) 7-5 7-6 (7-3)
Chung – 47/37
Djokovic – 36/57
Chung – 1/2
Djokovic – 2/9
BREAK POINTS WON
Chung – 6/10
Djokovic – 5/19
FIRST SERVE PERCENTAGE
Chung – 67
Djokovic – 62
PERCENTAGE OF POINTS WON ON FIRST/SECOND SERVE
Chung – 65/47
Djokovic – 65/39
Chung – 138
Djokovic – 128
|Joshua almost 2st heavier than Povetkin for Wembley bout|
|From salvation to the record books - Fisher revels in European Tour´s first 59|
|Lahm says Germany best for Euro 2024 as UEFA publishes report|
|Lopetegui backs Modric over Ronaldo for individual prizes|
|Goretzka to start against former club Schalke, confirms Kovac|
|Fisher shoots first 59 in European Tour history|
|Simeone defends Ronaldo after controversial Champions League red|
|Slater sees Storm into Grand Final, awaits fate over ´shoulder charge´|
|Hogg to miss Scotland´s November Tests following ankle surgery|
|Osaka through as Azarenka and Garcia crash out|
|Burgess weighing up legal options after being cleared in Rabbitohs investigation|
|Uncapped Cottrell and Gordon named in Wallabies squad|
|He´s done fantastic work - Mourinho hails Wolves boss Nuno|
|Joshua v Povetkin: No need for fireworks on AJ´s Wembley return|
|Six titles, 204 goals - Aguero´s incredible City career in Opta stats|
|Read to miss Argentina clash, Ioane brothers sign new deals|
|Pedro allays injury fears after Europa League clash|
|Dilly dilly to all the Cleveland fans! Mayfield promises further Browns success|
|Manchester United ´hell´ left Zaha depressed|
|Jackson hesitates in naming Mayfield as Browns´ starting QB|
|LeBron congratulates Browns for ending 635-day winless streak|
|Aguero Extension: 10 of the best goals from the Manchester City star|
|Aguero signs City contract extension until 2021|
|Stress from drink-driving charge may have contributed to Lloris injury – Pochettino|
|CBF backs Cruzeiro´s Dede appeal and suggests VAR investigation|
|The big Friday Premier League quiz|
|Red Sox clinch AL East with win over Yankees|
|Brighton star Knockaert reveals battle with depression|
|Bud Light beer fridges open after Browns snap 19-game winless streak|
|Browns end 635-day drought with first win since 2016 after downing Jets|
|Blue Jays overturn 8-2 deficit in improbable ninth-inning comeback|
|Colo Colo 0 Palmeiras 2: Scolari´s men poised for Libertadores SFs|
|Tour Championship would enhance successful year, says Tiger|
|Pogba: Man United getting better after winning run|
|What bothers me is that he has time to even do that – LeBron responds to Trump tweet|
|Cowboys most valuable NFL team for 12th successive year|
|Mkhitaryan aiming for glory with Europa specialist Emery|
|Sarri: Pedro´s injury is not too serious|
|This Week in U.S. Sports: Drama in Minnesota, a Judge returns and tragedy in Iowa|
|Tottenham will overcome rough patch – Lamela|
|Torreira impresses for Arsenal but leaves with knock|
|Gattuso urges Higuain to be less predictable with his movement|
|Steelers´ Brown: ´Obviously I don´t want to be traded´|
|Woods, Fowler share Tour Championship lead|
|LeBron James backs Serena Williams after US Open controversy|
|Thiem into St Petersburg quarters, but retiring Youzhny bows out|
|Wigan clinch home semi-final with win over Huddersfield|
|Can apologises following sexism accusations|
|De Bruyne expects to be back for Manchester derby|
|Celtic 1 Rosenborg 0: Griffiths late show lifts Hoops|
|Woods eagles 18 to make 65 at Tour Championship|
|Arsenal 4 Vorskla 2: Aubameyang at the double in entertaining triumph|
|Dudelange 0 AC Milan 1: Deflected Higuain goal spares Gattuso´s blushes|
|Birthday boy Rashid inspires Afghanistan to Asia Cup win|
|Sarri feeling sorry for ´unlucky´ Morata|
|Ryder Cup pick Garcia shoots 66 at Portugal Masters|
|Ronaldo, Zidane, Cantona and the most infamous red cards|
|Villarreal 2 Rangers 2: Arfield and Lafferty steal point for Gerrard´s men|
|PAOK 0 Chelsea 1: Willian strikes as Morata misfires|
|Rain delays Ostapenko in Seoul, Wang books Guangzhou semi|
|Pochettino backs Kane to end goal drought|
|We figured it out - 76ers´ Markelle Fultz rebuilds jump shot|
|Joshua: Povetkin my second-toughest fight|
|Relaxed Pochettino not pushing panic button|
|Why Manchester City fans must fix their relationship with the Champions League|
|Majestic Giorgi ends Wozniacki´s reign in Tokyo|
|Pochettino unwilling to risk Alli fitness|
|Bigger Champions League tests to come, warns Pogba|
|Eight for 10! - Nadeem spins his way to world-record figures|
|A 4-1 lead cut to 3-2 by VAR, but Quakes have no complaints after Atlanta defeat|