[42] In the semi-finals of the Ciudad de León rapid chess tournament in June, Carlsen played a four-game match against Viswanathan Anand, who was ranked No.

[50] Carlsen was close to winning the 2006 Norwegian Chess Championship outright, but a last-round loss to Berge Østenstad dropped him into another tie for first place with Agdestein.

[59] In the rapid chess tournament Rencontres nationales et internationales d'échecs in Cap d'Agde, France, he reached the semi-final, losing there to Sergey Karjakin.

[64] In May and June, he participated in the Candidates Tournament for the FIDE World Chess Championship 2007, facing Levon Aronian in a six-game match at standard time controls, which Carlsen drew (+2−2=2) by coming from behind twice.

[66] Immediately after the Biel tournament, Carlsen entered the open Arctic Chess Challenge in Tromsø, but his fourth-place result with +5=4 was a slight underperformance in terms of rating.

[84] Carlsen won the category 21 Nanjing Pearl Spring tournament, 2½ points ahead of second-place finisher Topalov, the world's highest-rated player at the time.

[86] In the Tal Memorial, played from 5 to 14 November, Carlsen started with seven straight draws, but finished with wins over former FIDE World Champion Ruslan Ponomariov and Peter Leko.

[89] Carlsen entered the London Chess Classic as the top seed in a field including Kramnik, Hikaru Nakamura, Michael Adams, Nigel Short, Ni Hua, Luke McShane and David Howell.

[103] In August, Carlsen played in the Arctic Securities Chess Stars tournament in Kristiansund, Norway., defeating Anand 1½–½ in the two-game final to win the championship.

In the 39th Chess Olympiad he scored 4½/8, losing three games, to Baadur Jobava, Michael Adams, and Sanan Sjugirov; these were his first losses with the black pieces in more than a year.

[111] On 5 November, Carlsen withdrew from the 2011 Candidates Tournament, having qualified as the highest rated challenger, citing dissatisfaction with the World Championship cycle format.

[116] Carlsen competed in the GM-A group of the 73rd Tata Steel Chess Tournament (formerly called the Corus chess tournament) on 14–30 January in Wijk aan Zee in an attempt to defend his title; the field included World Champion Viswanathan Anand, Levon Aronian, former World Champion Vladimir Kramnik, Alexander Grischuk, Hikaru Nakamura, Ruslan Ponomariov, among others.

Despite losing games with white against Anish Giri and reigning Russian champion Ian Nepomniachtchi, Carlsen finished with 8/13, including victories over Kramnik and tournament winner Nakamura.

[125] At the 74th Tata Steel Chess Tournament held on 14–29 January in Wijk aan Zee, Carlsen finished in a shared second place with 8/13, behind Aronian, and equal with Radjabov and Caruana.

[130][131] Carlsen won the London Chess Classic in December with five wins (over McShane, Aronian, Gawain Jones, Adams and Judit Polgár) and three draws (against Kramnik, Nakamura and Anand).

[135] On 1 February, Danish GM Peter Heine Nielsen joined the team of assistants who helped Carlsen prepare for the Candidates Tournament in March.

[145] On 8 May, Carlsen played an exhibition game at Oslo City against the people of Norway, assisted by a grandmaster panel consisting of Simen Agdestein, Jon Ludvig Hammer, and Leif Erlend Johannessen.

Billed as the strongest chess tournament ever held, the remaining 4 players in the event were Levon Aronian, Hikaru Nakamura, Veselin Topalov, and Maxime Vachier-Lagrave.

Carlsen continued his streak in April, winning Shamkir Chess with a score of 7/9 (+5−0=4), defeating Mamedyarov, Caruana, Vachier-Lagrave, Kramnik, and Rauf Mamedov.

[171] Carlsen played ten games for Norway in the 42nd Chess Olympiad, scoring five wins and five draws, as the Norwegians placed 5th among the 180 teams in the open event.

[182][non-primary source needed] Additionally, Leonard Barden, writing for The Guardian, said the performance was only matched by Fischer's 19/22 score at the 1970 World Blitz Championship.

[188][189] From 9 to 14 November, Carlsen faced Ding Liren in the 2017 Champions Showdown, a match consisting of 10 rapid and 20 blitz games, hosted by the Saint Louis Chess Club.

[268] Carlsen won his third Speed Chess Championship, beating five-time defending champion Hikaru Nakamura in the final to deny him a sixth consecutive title.

[275] In September, Carlsen won his fourth Speed Chess Championship title, defeating GM Alireza Firouzja in the finals held in Paris, France.

[492] In the January 2006 FIDE rankings, at the age of 15 years and 32 days, Carlsen attained a 2625 Elo rating, which made him the youngest person to surpass 2600[493] (the record has since been broken by Wesley So, Wei Yi, John M. Burke, and Yağız Kaan Erdoğmuş[494]).

In the July 2007 FIDE rankings, at the age of 16 years and 213 days, Carlsen attained a 2710 Elo rating, which made him the youngest person to surpass 2700 (the record has since been broken by Wei Yi).

[496][497] Carlsen's victory in the 2009 Nanjing Pearl tournament raised his FIDE rating to 2801, making him, aged 18 years and 336 days, at the time the youngest player ever to surpass 2800[85] (a record subsequently broken by Alireza Firouzja).

"[520][non-primary source needed] Carlsen has also stated that he follows in the traditions of Karpov and Fischer, but additionally mentions Reuben Fine as a player who "was doing in chess similar to what I am doing".

"[524] In a 2012 interview, Vladimir Kramnik stated that Carlsen's "excellent physical shape" was a contributing factor to his success against other top players as it prevents "psychological lapses", which enables him to maintain a high standard of play over long games and at the end of tournaments, when the energy levels of others have dropped.

[547] Agdestein's work consisted initially of finding sponsors and negotiating media contacts but, since 2011, he has taken over management tasks formerly performed by Carlsen's father Henrik.