Sobotka, who has spent the last four seasons with the Blues, was a restricted free agent, and the team planned to go to salary arbitration with him.
The forward totaled a career-high 33 points with nine goals and 24 assists in 61 games last season.
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As a restricted free agent, (Sobotka) wouldn't be able to leave the Blues for another NHL team unless traded as the fact that he's headed to arbitration makes him ineligible to be signed to an offer sheet by other teams. The KHL option certainly could be more lucrative for Sobotka at this point and there could also be some hurt feelings after months of talks went nowhere.
The restricted free agent was coming off of a three-year $3.9 million deal with the Blues and was likely expecting a raise.
The Blues announced today that the team re-signed forward Steve Ott to a two-year deal.
St. Louis finished the 2014 regular season with a 52-23 record, then lost to the Chicago Blackhawks in six games in the first round of the playoffs.