Praggnanandhaa, nicknamed Pragg, belied his age and his experience as he remained cool and collected, while Carlsen appeared to make mistakes to present opportunities to the Indian youngster.
And although the five-time world champion fought to get back into the game, Pragg didn’t give him an opening, eventually holding on for a famous victory in the rapid chess tournament.
When it became apparent a win was certain, the achievement appeared to dawn on Pragg, as he covered his mouth with his hand in shock.
It was Pragg’s first victory over Carlsen, and he became the youngest player to beat Carlsen since the superstar became World Champion in 2013.
He also became only the third Indian grandmaster to win against the Norwegian after Viswanathan Anand and Pentala Harikrishna.
“I’m just very happy,” he said afterwards.
When asked how he was going to celebrate, Pragg – with days of competition remaining in the tournament – was realistic given how late he was playing games being based in India: “I think it’s about just going to bed.”
“It’s about time to go to bed, as I don’t think I will have dinner at 2.30 in the morning.”
The result was probably not forecast before it began. Carlsen had won three games in a row as he looked to be warming up, while Pragg had finished Day 1 of the Airthings Masters with three straight losses.
However, when the two clashed, the 16-year-old grandmaster looked resolute, eventually beating the chess legend in 39 moves.
“I think yesterday wasn’t so good,” Pragg said after the match. “Today, I think my play was much better, so I hope this continues for the next two days.”
Pragg is one of the most up-and-coming stars of chess and has been tipped for great things from a young age.
In 2016, he became the youngest international master in history at age 10, and many people have predicted that he could be a title contender in the years to come.
His famous victory over Carlsen was the subject of praise from some well-known compatriots.
Five-time world champion Anand tweeted that he was “always proud of our talents,” also saying that it was a “very good day” for Pragg.
Elsewhere, Indian cricket player Sachin Tendulkar – widely considered one of the greatest batters of all time – also congratulated Pragg.
“What a wonderful feeling it must be for Pragg. All of 16, and to have beaten the experienced & decorated Magnus Carlsen, and that too while playing black, is magical!” Tendulkar wrote.
“Best wishes on a long & successful chess career ahead. You’ve made India proud!”
For Carlsen, it was a potentially damaging defeat in his hunt to add yet another trophy to his already prestigious collection.
The 31-year-old contracted Covid-19 in the days before the tournament, and he believes his game is being affected by the after-effects of the virus which he is still feeling.
“It’s been a little bit better today, but the first couple of days I was feeling like I’m OK, but I didn’t have the energy which made it hard to focus because every time I tried to think, I blundered. It was a little bit better today, but still pretty bad.”
Despite his stuttering form, Carlsen has managed to lift himself to second in the Airthings Masters standings, seven points behind leader Ian Nepomniachtchi.
Russian Nepomniachtchi is in prime position to qualify for the next stage of the competition, with eight players making the cut from the round-robin preliminary stage to the knockout which begins on Wednesday.