He became known as one of the best players in the KHL – winning the KHL's Golden Stick (MVP) award in 2018, and 2024 and finished the 2023–24 Season with 89 points (23 goals, 66 assists). His 89 points is the highest season total in the history of the KHL, beating out Sergei Mozyakin's record of 85 points. Gusev won the KHL's Gagarin Cup championship in 2017 with SKA Saint Petersburg.
Internationally, he has represented Russia on numerous occasions, winning a gold medal at the 2018 Winter Olympics and a silver medal at the 2022 Winter Olympics.
In the 2018–19 season, his last season under contract with SKA, Gusev posted a career and league-high 82 points, leading the KHL with 65 assists. He continued his offensive dominance in the post-season, contributing 19 points in 18 games before suffering a conference final defeat for the second consecutive season to CSKA Moscow. Through nine seasons in the KHL, Gusev is 10th all-time with 332 points in 391 games.
On 14 April 2019, Gusev signed a one-year, entry-level contract with the Vegas Golden Knights, instantly joining the club amid their first-round playoff series against the San Jose Sharks, remaining on the Golden Knights extended squad without playing for the club.[4]
On 29 July 2019, Gusev as a restricted free agent, was traded by the Golden Knights to the New Jersey Devils in exchange for a third-round pick in 2020 and a second-round pick in the 2021 NHL Entry Draft. He immediately agreed to terms with the Devils on a two-year, $9 million contract with an average annual value of $4,500,000.[5] In the following 2019–20 season, Gusev made an immediate offensive impact with the rebuilding Devils, leading the club with 31 assists and placing second in points with 44 through 66 games before the remainder of the regular season was cancelled due to the COVID-19 pandemic.
With the Devils missing the postseason, Gusev returned to action in the delayed 2020–21 season and struggled to replicate the previous season's campaign offensively, posting just two goals and five points through 20 games. On 9 April 2021, the Devils placed Gusev on unconditional waivers in order to mutually terminate the remainder of his contract.[6]
Florida Panthers
On 11 April 2021, Gusev signed as a free agent to a one-year, $1 million contract with the Florida Panthers.[7]
Return to SKA
As a free agent over the summer and approaching the 2021–22 season, Gusev opted to continue his career in the NHL, signing a Professional Tryout contract in accepting an invitation to attend the Toronto Maple Leafs training camp on September 18, 2021.[8] Gusev was later released from his tryout on October 5, 2021.[9] with no other NHL teams expressing an interest he opted to return to the KHL, with his former team SKA Saint Petersburg.
Gusev enjoyed two offensively productive seasons with SKA, before opting to leave the club as a free agent at the conclusion of the 2022–23 season on 30 April 2023.[10]
Dynamo Moscow
On 18 July 2023, Gusev as a free agent agreed to terms on a one-year contract with his fifth KHL club, HC Dynamo Moscow, for the 2023–24 season.[11] After a highly productive debut season with Dynamo, Gusev was re-signed to a one-year contract extension on 1 August 2024.[12]