[2] However, he once again lost his challenge for the World Chess Championship title after losing to Ding Liren in 2023 during the 4th game of tiebreaks.

Nepomniachtchi's first coaches were his uncle Igor Nepomniashchy, Valentin Evdokimenko, international master Valery Zilberstein, and grandmaster Sergei Yanovsky.

[4] In 2002, Nepomniachtchi also won the World Youth Chess Championship in the U12 category, edging out Magnus Carlsen on tiebreak score.

[5] In 2007, he finished second in the C group of the Corus Chess Tournament in Wijk aan Zee[6] earning his first grandmaster (GM) norm.

The third and final norm required for the GM title was won at the 5th Vanya Somov Memorial – World's Youth Stars tournament in Kirishi.

[7] Nepomniachtchi won the latter event, edging out Rauf Mamedov, Parimarjan Negi and Zaven Andriasian on tiebreak score.

[16] In November 2011, Nepomniachtchi tied for 3rd–5th with Vasily Ivanchuk and Sergey Karjakin in the category 22 Tal Memorial in Moscow.

[19] The following month, Nepomniachtchi finished second to Shakhriyar Mamedyarov in the World Rapid Chess Championship, held in Khanty-Mansiysk.

[24][25] At the SportAccord World Mind Games, held in December 2014 in Beijing, he won the gold medal in the men's Basque chess tournament.

[26] In April 2015, he won the Aeroflot Open for the second time in his career, edging out Daniil Dubov on tiebreak, having played more games with the black pieces, and earned a spot in the 2015 Dortmund Sparkassen Chess Meeting.

[33] At the 42nd Chess Olympiad, held in 2016, he won the team bronze medal and an individual silver playing board 4 for Russia.

At the Chess World Cup 2017, Nepomniachtchi defeated Mladen Palac and Baskaran Adhiban in the first and second rounds, but lost to Baadur Jobava in tiebreaks.

[34] On 10 December 2017, Ian won a chess game against world champion Magnus Carlsen at the super tournament in London.

In July 2018, he won the 46th Dortmund Sparkassen Chess Meeting, scoring 5/7 (+3–0=4) to finish a point ahead of his nearest competitors.

[38] Over the course of 2019, he participated in the FIDE Grand Prix series, which was part of the qualification cycle for the 2020 World Chess Championship.

[41] From 26–28 December 2021, Nepomniachtchi participated in the 2021 FIDE World Rapid Championship, where he ended as one of the joint leaders with 9½/13 points, and scored second place after tiebreaks.

[42] In December 2021, Nepomniachtchi played a friendly game with Nornickel president Vladimir Potanin, which ended with victory for the grandmaster in the 38th move.

During the FIDE World Chess Championship 2023, Nepomniachtchi had a tied score of 7–7 with Ding Liren in the classical portion of the match.

[49] In May 2023, Nepomniachtchi participated in the Superbet Chess Classic 2023, finishing in 9th place, after losing to Fabiano Caruana, Alireza Firouzja, and Maxime Vachier-Lagrave.

[52] During round 11 of the World Blitz Chess Championship 2023, controversy arose after Nepomniachtchi faced off against fellow compatriot Daniil Dubov, with both players agreeing to a 13-move draw after playing a series of knight moves.

After an investigation by FIDE, the chief arbiter penalized both Nepomniachtchi and Dubov on the basis that they had prearranged the draw, ruling the game with a 0–0 result.

[60] In December, he played in the Champions Chess tour, finishing in second place after losing in the finals to Magnus Carlsen.

Later that month, Nepomniachtchi was crowned the joint winner of the World Blitz Championship alongside Magnus Carlsen when the pair controversially agreed to share the title after three tiebreak matches in the final ended in draws.