He previously played for the Washington Capitals and Carolina Hurricanes in the National Hockey League (NHL) and Traktor Chelyabinsk of the KHL.

Kuznetsov won the Stanley Cup with the Capitals in 2018, leading the playoffs in point-scoring with 32 points, the most by any player in a single postseason since Evgeni Malkin in 2009.

During the 2015–16 season, Kuznetsov was named to his first All-Star Game as a replacement for Alexander Ovechkin, who pulled out due to a lower-body injury.

[9] Kuznetsov's series-clinching overtime winner in Game 6 against Pittsburgh secured the Capitals’ first berth in the Eastern Conference Finals since 1998, ending years of playoff failure against the Penguins.

[11] Kuznetsov led the league with 32 points in 24 appearances in the 2018 postseason, but lost to linemate and team captain Alex Ovechkin in the Conn Smythe Trophy competition.

[12] "In helping deliver a championship Washington had wanted for more than 40 years, Kuznetsov was arguably the Capitals' most instrumental player.

The 26-year-old, fifth-year pro finished with a playoff-leading 32 points, including his 20th assist in Thursday night's series-clinching 4–3 win over the Vegas Golden Knights in Game 5.

He's gonna be in the Hall of Fame and maybe one of those pictures in Hall of Fame I'm gonna be somewhere around him just after we score.On 14 September 2019, the NHL suspended Kuznetsov for three games for cocaine use after video surfaced on social media that showed Kuznetsov and another man sitting at a table that appeared to have lines of cocaine on it; the NHL termed the offense "inappropriate conduct.

[18] On 4 March, Kuznetsov cleared waivers and was loaned to the Hershey Bears, the Capitals' American Hockey League (AHL) affiliate.

[19] On 8 March 2024, before playing a game with Hershey, Kuznetsov was traded by the Capitals to the Carolina Hurricanes in exchange for a 2025 third-round draft pick.

[23] As a free agent, Kuznetsov returned to his homeland in resuming in career in the KHL, agreeing to a lucrative four-year contract with SKA Saint Petersburg on 31 July 2024.

"[25] Kuznetsov has played in the shadows of fellow Russian Alexander Ovechkin, but his talent began to gain attention.

[29]Of his own approach to playing, the recognition he's getting from teammates on his talent, and his preference for fun over awards Kuznetsov says:[30] To be MVP, you have to work hard 365 [days] in a year, but I’m not ready for that.

His "cellies" (hockey slang for "celebrations") have most prominently included the prancing bird – and earlier the kayak, push-ups, and playing dead.

[31] Kuznetsov debuted the bird dance at the 2016 World Cup when he scored an end-to-end goal against Matt Murray of Team North America.

[31] Kuznetsov played for Russia at the 2010 World Junior Ice Hockey Championships held in Saskatchewan, Canada.

[38] Kuznetsov then served as team captain for Russia at the 2012 World Junior Championships, the third year in a row he participated in the tournament.

[39] On 23 August 2019, the IIHF announced that it had suspended Kuznetsov for four years after he had tested positive for cocaine, retroactive to 13 June 2019.

[43] Kuznetsov married Anastasiya (Nastya) Kuznetsova (née Zinov'eva) in 2011 in a ceremony at Traktor Ice Arena.