How Carlsen’s Blunder To Duda Ended An Amazing Unbeaten Streak

The most fascinating game of 2020 is the standard game between World Champion GM Magnus Carlsen and GM Jan-Krzysztof Duda (world number-15) in the Altibox Norway Chess tournament. Carlsen lost!

This game may rank among the most surprising outcomes in chess of all time. The loss was Carlsen’s first defeat in more than two years, and it occurred in his native Norway. The game, the blunder, the streak, and the tournament are now part of the significant lore of chess, and the reflections by both players help to put the outcome in perspective.

The Game

The game was played in the fifth round of the 8th Altibox Norway Chess tournament on Saturday, October 10, 2020. After playing an unusual variation of the Caro-Kann in the opening, Carlsen chose to exchange a rook for a bishop to open the b-file file to set up the potential for an aggressive attack on White’s king. However, with 21…h4, Carlsen allowed Duda to consolidate his position in the next few moves. The board below is set after White's 31st move.

The Blunder

About Carlsen’s move 31…Qxa2, Duda said: “He obviously blundered” because the Polish GM was able to defend his king by moving his queen to c2 and then capture Carlsen’s remaining rook on the back rank with 33.Re8+. (Why Carlsen cannot capture with 33…Rxe8 is explained in the tournament report—see the link below—and is worth taking the time to review.)

Carlsen continued to play a rook and exchange down, but the material imbalance was too severe. Carlsen resigned after Duda’s 63rd move. Because the purpose of this post is not to analyze the game itself but to examine the significance of the loss, I instead refer you to comprehensive analyses about the game by Chess.com experts:

• The detailed tournament report
• A thorough video analysis 

The Streak

The loss was Carlsen’s first one since July 31, 2018, when he lost to Azerbaijani GM Shakhriyar Mamedyarov at the Biel Chess Festival. The unbeaten streak, when Carlsen scored 42 wins and 83 draws, is a significant record. It lasted for two years, two months, and 10 days and extended for 125 classical games. How long will it stand?

The Tournament

The tournament began on October 5, 2020 in Stavanger, Norway, and ended on October 16. It was a double round-robin with six players—the other four were GMs Levon Aronian, Fabiano Caruana, Alireza Firouzja, and Aryan Tari. The time control for each standard game was two hours for all moves with a 10-second increment per move after move 40. (The tournament also included an armageddon game if a standard game ended in a draw.)

The Reflections

After ending Carlsen's 125-game unbeaten streak, Duda commented: "I'm very happy, obviously! I didn't expect to win this game at all…. I almost blundered checkmate in one move."

A day after the loss, Carlsen and Duda had a rematch that the world champion won. After his win, Carlsen reflected on his loss in the previous game and the end of his unbeaten streak:

Losing wasn’t that big a deal, like a hundred games and then the record streak. Those were the ones that I really cared about. And after that, I knew that I was going to lose at some point, and especially I was taking risks in my games. But anyway, losing a poor game yesterday is obviously unpleasant no matter what’s at stake. I was mostly upset at losing in general, not so much the streak. But at least now there is no streak, so I don’t have to worry about that.

Now it's your turn. Are you amazed by Carlsen's unbeaten streak? How long do you think it will last?