At the conclusion of the season, Barbashev was selected first overall by the Moncton Wildcats in the 2012 Canadian Hockey League Import Draft.

[6] Barbashev made his professional debut in the 2015–16 season with the Blues' American Hockey League (AHL) affiliate, the Chicago Wolves.

Barbashev likewise did not match his record totals from the prior year, but posted 10 goals and 29 points in 59 games.

By the beginning of the 2023 Stanley Cup playoffs, he was playing on the team's top line alongside Jonathan Marchessault and Jack Eichel.

He had 7 goals and 11 assists in Vegas' deep run to the 2023 Stanley Cup Finals, where they defeated the Florida Panthers to take the championship, the team's first and Barbashev's second.

The team had earlier that day traded veteran forward Reilly Smith in order to create the necessary room for Barbashev's contract.

[7] Barbashev's older brother Sergei plays for Admiral Vladivostok of the Kontinental Hockey League (KHL).