Masin agreed to terms on a contract with KHL side Amur Khabarovsk on Monday, The Peterborough Examiner reports.
Masin has been sent to the minors.
Masin agreed to sign a one-year, two-way contract with the Lightning on Wednesday.
Tampa Bay didn't extend Masin a qualifying offer Tuesday.
Masin (undisclosed) has suited up in three games for AHL Syracuse in 2017-18, picking up four penalty minutes while failing to record a point.
Masin (undisclosed) will begin the 2017-18 campaign on injured reserve, Erik Erlendsson of LightningInsider.com reports.
The Lightning have signed Masin to a three-year entry-level contract. He was drafted by Tampa 35th overall in 2014.
Dominik Masin went to the Tampa Bay Lightning with the 35th overall pick of the 2014 NHL Entry Draft.
Masin is a force in the defensive end, and his offensive game has started to come around as well, creating some buzz for himself as the year went along. He is fundamentally sound on the defensive side, with great awareness. Masin is a hard-nosed defenseman who bangs bodies, can effectively block shots, defend one-on-one situations and clear the crease. He tallied 102 penalty minutes this past season. While he still needs to improve his foot speed and overall offensive skill set, evaluators have taken note of his uptick in offensive production: from nine points to 21 in the 2013-14 season.