The veterans had to clear waivers and did so as the Blackhawks were on the ice for practice.
Leighton, 33, complied a 20-15-6 record along with a 1.74 goals against average and .934 save percentage with Donbass Donetsk of Russia's KHL last season. He was signed as a free agent during the summer with the intention to provide depth and start in Rockford.
Leighton has appeared in 105 career NHL regular season games and posted a 35-41-14 record with the Blackhawks, Nashville Predators, Philadelphia Flyers and Carolina Hurricanes. Leighton does hold a NHL record with most shutouts in a postseason series with three against Motreal in the 2010 Eastern Conference Final with Philadelphia.
The 28-year-old Regin, scored four points in 17 regular season games for the Blackhawks and skated in five playoff games in 2014. Regin was acquired last February with Pierre-Marc Bouchard from the New York Islanders for a fourth round draft pick and has recorded 23 goals and 43 assists in 239 NHL games with the Blackhawks, Islanders, and Ottawa Senators.
The Blackhawks' current roster now includes 14 forwards, 11 defenseman and two goaltenders.