Dommaraju Gukesh beat Nodirbek Abdusattorov in the battle of the teenage chess prodigies at the Norway Chess tournament on Sunday.
Seventeen-year-old Gukesh and 18-year-old Abdusattorov could not be separated during the classical portion of the match with it ending in a draw.
Indian chess grandmaster Gukesh, who last week beat world No.1 Magnus Carlsen on his 17th birthday, eventually prevailed in an armageddon game -- which is used in the tournament to separate ties -- to claim an important victory in round five.
Gukesh said he thought the outcome and his performance was "pretty good."
"In the armageddon, he played Catalan which he's not very familiar with, and I got a very pleasant position out of the opening and there was no way I could lose," he said.
According to chess.com, in the event of a tie "players contest an armageddon game where White has 10 minutes on their clock and Black has seven, with a one-second increment starting on move 41. Black has draw odds. The player who played White in the classical game plays White in the armageddon."
The victory means Gukesh rises to fourth in the standings, while Uzbekistani grandmaster Abdusattorov slips to eighth.
In the tournament, which is held in Stavanger, Norway, 10 players compete in a single round-robin tournament. The winner will receive approximately $68,400, with second place winning $36,500.
Gukesh faces Dutch grandmaster Anish Giri in round six on Monday, while Abdusattorov faces the US' Fabiano Caruana.
Elsewhere, American grandmaster Hikaru Nakamura regained the world No. 2 spot for the first time since 2015 with a victory over Aryan Tari on Sunday.
Nakamura dominated throughout against Tari, eventually winning 3-0, to move to second in the world after Caruana had moved above him a day before.
"It was very similar to the Gukesh game [Nakamura won 3-0]," he said afterwards.
"At some point, I started using time, and every move that was played by my opponent was not the move that I was expecting, and finally, I just started moving quickly."
Afterwards, Nakamura was informed that he'd beaten Tari on his birthday. "Normally, on your birthday, you do much worse," remembering a London Chess Classic game where he also lost on his birthday against Wesley So. "So I know how it feels."
Carlsen claimed his own important victory in round five, beating Giri in the armageddon round after their classical game ended in a draw.
Carlsen admitted afterwards that after a low-key beginning to the tournament in his home country, his victory on Sunday was a part of his plan to claw his way back into contention.
"I am on step 2 in my plan to get back into the tournament," Carlsen said, per chess journalist Tarjei J. Svensen.
"Plan 1 was to change my looks, which didn't work very well yesterday. The second part of my plan is to do what I did in a time when I had some success by just sacrificing a pawn as quickly as possible and focus on the center and attack after that. Let's see if it works."
