World No. 1 Magnus Carlsen returned to winning ways with a crushing victory over reigning classical world champion D Gukesh, sending the young Indian to the bottom of the standings, while R Praggnanandhaa stayed second after beating Vincent Keymer in Armageddon at the Norway Chess here.
Seven-time Norway Chess champion Carlsen, who had endured a sluggish start to the tournament, climbed from last to sole fourth with 4.5 points after bagging three full points, while a dejected Gukesh slipped away quietly from the playing hall through a side exit, leaving scores of young fans waiting for autographs.
Going into Friday's rest day, Alireza Firouzja remained comfortably on top despite suffering his first defeat of the event -- an Armageddon loss to Wesley So after their classical game ended in a draw.
Firouzja still collected a valuable point to move to 8.5, maintaining a healthy 2.5-point lead over sole second-placed Praggnanandhaa on six points.
American Wesley So sits third on 5.5 points, a point ahead of Carlsen, while Keymer is on four.
At the bottom is reigning world champion Gukesh on 3.5 points, as the tournament threatens to turn into another nightmare campaign for the young Indian ahead of his world title defence against challenger Javokhir Sindarov later this year.
There were no table-slams or dramatic "Oh my God!" moments from Carlsen this time, unlike his emotional loss to Gukesh last year, as the Norwegian great clinically converted his advantage with the black pieces.
"I wouldn't say I was super-motivated today. I kind of had enough after playing really poorly for three days in a row with very little time. Today, I didn't have a lot of expectations, but I was happy with the way things went in the opening," Carlsen said after the game.
The five-time world champion admitted that he was surprised by Gukesh's choice of opening.
"I was surprised by Nf3. I wasn't sure if I couldn't take it, but it seemed like a draw at most. He sometimes plays a little too ambitiously and I think he did that today as well. He wanted to prove a serious advantage, and I'm not sure there was one. Eventually, he played himself into some trouble and I gradually took over," Carlsen added.
Carlsen also revealed there was still some anxiety late in the game despite his dominant position.
"Right at the end I was a little worried (if) I was allowing him to take a knight with check. I was thinking, This happened against Praggnanandhaa yesterday, it happened against Gukesh last year -- am I actually missing something? But if I was, he didn't find it," added the Norwegian great.
Gukesh, who turned 20 just hours after the defeat, heads into the rest day with plenty of uncomfortable questions to confront before his fifth-round showdown against compatriot Praggnanandhaa, who has looked far tougher temperamentally and markedly better equipped to absorb the relentless pressure and challenges of Norway Chess so far.
Praggnanandhaa and Keymer both let winning chances slip in what could have been a decisive classical game before the Indian sealed the Armageddon tie-break in just 17 moves.
"The Armageddon went smooth," Praggnanandhaa said after pocketing 1.5 points to consolidate his hold on sole second place.
For Keymer, Armageddon is turning into a recurring nightmare, with the Norway Chess debutant now losing four successive tie-breaks.
In Norway Chess Women, Divya Deshmukh suffered her first Armageddon defeat after winning three straight tie-breaks, going down to defending champion Anna Muzychuk. The loss dropped the World Cup winner from sole second to a three-way tie for third on 5.5 points.
Koneru Humpy, meanwhile, continued to struggle, losing another Armageddon game to Zhu Jiner and remaining last in the six-player field.
The standings are headed by Bibisara Assaubayeva on seven points, followed by Muzychuk, Divya and Zhu on 5.5 each. Reigning women's world champion Ju Wenjun is on four points, while Humpy trails on three.
Results (Round 4): Open - Wesley So (USA, 5.5) bt Alireza Firouzja (Fra, 8.5); D Gukesh (Ind, 3.5) lost to Magnus Carlsen (Nor, 4.5); Vincent Keymer (Ger, 4) lost to R Praggnanandhaa (Ind, 6).
Women – Bibisara Assaubayeva (Kaz, 7) bt Ju Wenjun (Chn, 4); Divya Deshmukh (Ind 5.5) lost to Anna Muzychuk (Ukr, 5.5); Koneru Humpu (Ind, 3) lost to Zhu Jiner (Chn, 5.5).
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