An exciting 12th round with four decisive results on Saturday left only two players in contention to win the Fide Candidates tournament being held in Yekaterinberg, Russia.
Dutch Grandmaster Anish Giri continued his run of excellent form and beat US GM Fabiano Caruana with Black, but could not catch up with Nepomniachtchi.
The Russian Grandmaster got the better of Chinese Wang Hao. Frenchman Maxime Vachier-Lagrave and Ding Liren of China also won.
Nepomniachtchi leads the chart with eight points followed by Giri on 7.5.
The Candidates chess is being held from the eighth round. The tournament was postponed last March after seven rounds due to the raging Covid-19 pandemic.
On Friday, Giri moved up to second place after beating Liren.