Reigning world chess champion Magnus Carlsen has lost to 17-year-old wonderkid Nodirbek Abdusattorov from Uzbekistan in their meeting in the rapid-format version of the game.
Abdusattorov administered the defeat to the Norwegian at the World Rapid Championship on Tuesday.
Carlsen is the reigning champion at the tournament being held in the Polish capital Warsaw.
But with his win, Abdussattorov now leads alongside Carlsen's recent World Chess Championship victim Ian Nepomniachtchi on 8/10 with three rounds to go.
Interviewed immediately after his greatest career achievement, the youngster was humble in victory.
"I was a little bit lucky," claimed the shy teenager. "Because he could [only] force a draw."
"Overall this game was pretty much equal all the way until the end."
"The tournament isn't finished yet," Abdussattorov reminded us. "I'm concentrating on the next round."
Elsewhere, he conceded it was a "huge victory" over Carlsen but revealed that he was "expecting to play better in the next rounds".
Trailing on 8.0 points, Carlsen has a tough task to retain the crown he won in 2014, 2015 and most recently in Moscow in 2019 before the pandemic.
Thanks to Covid, there was no edition of the tournament in 2020 which will conclude on December 30 this year.
Carlsen recently hinted that he played his last World Chess Championship match against Nepo as it had "been clear to me for most of the year" that it was time to call it a day in the competition.
"It doesn’t mean as much anymore as it once did. I haven’t felt that the positive outweighs the negative," he revealed to Chess 24.
The 31-year-old said that only by facing someone such as Iranian-born French teenager Alireza Firouzja can he be motivated to try and land the title a sixth time.
But Abdusattorov might have now joined that shortlist after this afternoon's exploits.