Rubtsov, 22 (6/27/1998), spent the 2020-21 season on loan to HK Sochi of the KHL, where he had three goals and eight assists for 11 points in 46 games. He had split the 2019-20 season with the Flyers and their American Hockey League affiliate, the Lehigh Valley Phantoms, until both leagues paused their season in March of 2020. Rubstov had two goals and 11 assists for 13 points in 42 games with the Phantoms, while also appearing in four games with the Flyers.
Rubtsov appeared in 14 games for the Phantoms during an injury-shortened 2018-19 season, collecting six goals and four assists for 10 points. It was his first season as a professional in North America following a junior career that included parts of two seasons in the Quebec Major Junior Hockey League and time in Russia's MHL and KHL.
A 6-0, 187-lb native of Chekhov, Russia, Rubtsov was selected by the Flyers in the first round (22nd overall) of the 2016 NHL Entry Draft.