Chigaev was born in
Kemerovo. He played on the Russian team that won the World Youth Under 16 Chess Olympiad in 2012. Chigaev also won an individual gold medal as the best player on the second board. In 2015 he won the Vanya Somov Memorial - World's Youth Stars tournament in
Kirishi. In 2018, he played on team Molodezhka of
Tyumen which took the bronze medal in both the Russian Team Championships Premier League and the European Club Cup. In January 2019 Chigaev shared second place with
Andrey Esipenko and
Benjamin Gledura in the
Tata Steel Challengers tournament in
Wijk aan Zee, the Netherlands scoring 8½ points from 13 games. He competed in the
FIDE World Cup 2019 as one of the nominees by the president of FIDE. Chigaev was paired against
Parham Maghsoodloo and lost to him by 2–0 and therefore was eliminated from the tournament in the first round. In October 2020, Chigaev won the Higher League of the 73rd Russian Chess Championship in
Sochi with a score of 6.5/9 and qualified for
Russian Chess Championship Superfinal later in the year. Chigaev won silver in the
Chess.com competition at the
2023 Olympic Esports Week. ==Notes==