 Leighton served as Sergei Bobrovsky's backup for the remainder of the season, but did not see any ice-time.An unrestricted free agent the following the season, on August 19, 2013, Leighton signed a one-year contract with HC Donbass of the Kontinental Hockey League (KHL).On May 28, 2014, Leighton signed a one-year contract with HC Sochi of the KHL.