 Leighton's contract was subsequently voided after an illness prevented him from attending training camp.On August 18, 2014, Leighton signed a one-year, two-way contract with the team he began his NHL career with, the Chicago Blackhawks.During the Blackhawks' training camp, Leighton was assigned (along with centre Peter Regin) to Chicago's AHL affiliate, the Rockford IceHogs, after clearing waivers.