BUDAPEST: Five-time world champion Magnus Carlsen is in danger of losing the world No. 1 spot he has held for 15 years after suffering a defeat to Armenia's Haik Martirosyan on the third day of the Fast Classical competition at the Total Chess World Championship Tour Pilot here.
The 35-year-old Norwegian GM has held the top spot since July 2011. However, after five draws and a loss in the Fast Classical section, Carlsen has lost 15.8 rating points and slipped to 2807.2 in the live ratings.
In-form American Fabiano Caruana is closing in on Carlsen. The American GM has registered five wins and two draws, gaining 17 points to reach 2800 and is just 7.2 points behind Carlsen.
The live ratings are updated in real time while FIDE publishes a monthly rating as well.
Playing Carlsen for the first time in a classical FIDE-rated game, Martirosyan defeated the Norwegian in 41 moves in the first game. Playing with white, Martirosyan built a dangerous attack and eventually broke through to secure the victory.
Carlsen was in time trouble early in the game and, with the clock ticking, he was forced to make hurried moves that led to errors. He eventually resigned.
The two GMs settled for a draw in the reverse fixture.
"It was a dream for me just to play him in a classical game but to win is even more special. I will think about this moment many times it is very special for me.
"It was an amazing day and I will remember this day for the rest of my life," Martirosyan said.
With the win and a draw, Martirosyan moved to 10 points, taking the outright lead in Group C, while Carlsen slipped to fifth place.
The top four from each group will compete for the title, while the rest will play for classification.
Meanwhile, Arjun Erigaisi registered a win and a draw against Wesley So.
The Indian GM was under pressure in the first game, but So, who was in a winning position earlier, declined a draw before blundering and resigning a move later.
"It was an interesting game. In the middle game I felt I did a very good job by sacrificing the exchange..partly I blundered also but then I got very good compensation, I had such good control.
"It shouldn't have gone the way it did then I totally messed up. I did a good job of not panicking," Erigaisi said.
The two drew the reverse fixture.
The 23-year-old Indian is third in Group D, behind leader Maxime Vachier-Lagrave and Hans Niemann.
R Vaishali registered her first win in the Fast Classical section of the tournament. The Indian GM, who will challenge China's Ju Wenjun for the Women's World Championship title next year, defeated Kazakh GM Bibisara Assaubayeva with white pieces.
Vaishali had lost to Bibisara in the first game of the day. Despite the win, Vaishali remains at the bottom of Group D.
Vaishali's brother, R Praggnanandhaa, extended his winless streak as he drew twice with Vladislav Artemiev. The Indian is on four points, having drawn four games and lost two.
"Obviously the results aren't great I'm still trying to adapt," Praggnanandhaa said.