Pokka will spend the 2018-19 campaign playing for Avangard Omsk in the KHL.
Pokka was traded from the Blackhawks to the Senators on Thursday for Chris DiDomenico.
Pokka was sent down to AHL Rockford on Monday.
Pokka cleared waivers and was assigned to AHL Rockford on Saturday, Mark Lazerus of the Chicago Sun-Times reports.
The Blackhawks placed Pokka on waivers Friday, James Mirtle of The Athletic Toronto reports.
The Blackhawks agreed to terms with Pokka on a one-year contract extension Tuesday, The Athletic's Scott Powers reports.
Pokka was sent back down to AHL Rockford on Sunday, Tracey Myers of CSN Chicago reports.
Pokka was recalled by the Blackhawks on Friday, Tracey Myers of CSN Chicago reports.
Pokka was assigned to AHL Rockford on Thursday, Brian Sandalow of the Chicago Sun-Times reports.
Pokka was recalled by the Blackhawks Tuesday.