Dallas Stars

Nichushkin played his first regular season NHL game on October 3, 2013, against the Florida Panthers.^[1] He scored his first career NHL goal on November 3, against Craig Anderson of the Ottawa Senators.^[2]

Following a strong rookie season, registering 14 goals and 20 assists, Nichushkin suffered from hip and groin soreness in the beginning of his sophomore campaign in 2014–15. Five games into the season, Nichushkin opted for hip surgery, which was performed on November 18, 2014.^[3] He rehabbed in New Jersey and re-joined the team in March 2015, practicing in a red no-contact jersey.

CSKA Moscow

As a restricted free agent following the conclusion of his entry-level deal in the 2015–16 season, Nichushkin and the Stars failed to agree to common grounds in contract negotiations. Unhappy with his role within the Stars lineup, his KHL rights were traded from Dynamo Moscow to CSKA Moscow on September 20, 2016. He subsequently signed a two-year contract to return to the KHL with CSKA, with his NHL rights to be kept by the Stars.^[4]

Return to Dallas

After two seasons with CSKA, Nichushkin returned to the Stars organization, in agreeing to a two-year, $5.9 million contract on July 1, 2018.^[5] In his return to the Stars in the 2018–19 season, Nichushkin recorded 10 assists in 54 regular season games, averaging 11:55 time on ice per game. He skated in one game during the playoffs with the Stars and failed to record a point.

After a disappointing 2018-19 campaign, failing to score a goal through 57 games, Nichushkin was placed on unconditional waivers by the Stars and subsequently bought out from the remaining year of his contract with the team on 30 June 2019.^[6]

Colorado Avalanche

Nichushkin signed a one-year, $850k contract with the Colorado Avalanche on August 19, 2019. Nichushkin scored his first goal in two years on November 23. In his first season with the Avalanche, generally perceived to be a successful one, Nichushkin especially received high praise from many hockey analytics proponents for his high rankings in many metrics, especially defensive metrics. ^[7] Nichushkin finished the 2019–20 season with 13 goals and 27 points while leading all forwards in the NHL in defensive goals above replacement.^{[citation needed]} Such strong defensive play helped Nichushkin to receive votes for the Frank J. Selke Trophy, the award given to the best defensive forward in the NHL, finishing eighth in voting.^[8]

On October 10, 2020, the Avalanche re-signed Nichushkin, who was a restricted free agent, to a two-year, $5 million contract extension.^[9]

In his third season with Avalanche, Nichushkin elevated in a top-six forward role, scored a career-best 52 points in 62 games, adding 15 points in 20 playoff games. He placed third on the team with nine playoff goals to help the Avalanche claim their first Stanley Cup in 21 years.

On July 11, 2022, Nichushkin signed an eight-year, $49 million extension to stay with the Avalanche. The following season, Nichushkin continued his strong play with the Avalanche, recording 47 points in 53 games as Colorado won the division and matched up in the opening round of the playoffs against the expansion Seattle Kraken, who were making their post-season debut as a franchise. Nichushkin played in two games, recording one goal in Game 2. Shortly after, Nichushkin abruptly stepped away from the team for "personal reasons" amid an incident at a Seattle hotel. Nichushkin was reportedly found with an Eastern European woman suffering from severe alcohol intoxication; the woman was reported to be either a prostitute or victim of human trafficking. Despite the nature of the incident, the NHL and Seattle Police reported that Nichushkin would not face criminal charges and Nichushkin would have played if the Avalanche had moved on to the second round.^[10][11] Ultimately, the Kraken would claim an upset series victory, defeating the Avalanche in seven games.^[11]

On January 15, 2024, it was announced that Nichushkin had entered the NHL/NHLPA Assistance Program and would be unavailable for the team for an indefinite period while he received care from the Player Assistance Program.^[12] After completing the program, Nichushkin returned to the Avalanche lineup on March 8, in a game against the Minnesota Wild where he scored the overtime game winning goal.^[13] On April 28, Nichushkin recorded his first career NHL hat-trick in a 5–1 win over the Winnipeg Jets in game 4 of the first round of the 2024 Stanley Cup playoffs.^[14] The Avalanche would defeat the Jets in five games, but during the series against the Stars two weeks later, Nichushkin's season ended when he was given a six month suspension for having violated the terms set forth by the Player Assistance Program, and again entered the program, this time undergoing Stage 3.^[15]