Gambrell was sent to AHL Cleveland on Wednesday, per Mark Scheig of The Hockey Writers.
Gambrell was summoned from AHL Cleveland on an emergency recall Monday.
Gambrell was placed on waivers by the Blue Jackets on Wednesday, James Mirtle of The Athletic reports.
Gambrell signed a one-year, two-way contract with Columbus on Tuesday.
Gambrell (concussion) was placed on waivers Sunday, according to Chris Johnston of TSN.
Gambrell "won't be available for a while" due to a concussion, Terry Koshan of The Toronto Sun reports.
Gambrell inked a one-year, $775,000 contract with Toronto on Monday, per PuckPedia.
Gambrell recorded an assist in Saturday's 7-4 win over the Lightning.
Gambrell scored his second goal of the season in Tuesday's 2-1 loss to the Bruins.
Gambrell earned an assist against the Red Wings on Monday.