Rubtsov was initially named to Flyers Return to Play squad to participate in training camp in preparation for the playoffs.
He was left off the final roster and on 23 August 2020, he was loaned to Russian club, HC Sochi of the KHL, until the commencement of the delayed 2020–21 North American season.
[5] Rubtsov continued with HC Sochi and was later determined to remain with the club for the duration of the campaign, finishing with 3 goals and 11 points through 46 regular season games.
With a year still remaining on his entry-level contract with the Flyers, in the off-season Rubtsov's KHL rights were traded from Sochi to SKA Saint Petersburg on 17 August 2021.
[8] Un-signed in North America, Rubtsov opted to return to his homeland to continue his career, signing a one-year, two-way contract with KHL outfit, HC Spartak Moscow, on 24 August 2022.