The Maple Leafs placed forward Nicholas Shore on waivers Tuesday, indicating Marner's return could be imminent.
The 22-year-old, who led Toronto in scoring each of the past two seasons, will miss his 11th straight game when the Maple Leafs play the Philadelphia Flyers at Wells Fargo Center on Tuesday (7 p.m. ET; ESPN+, TVAS, NBCSP, TSN4, NHL.TV). Toronto then plays a home game Wednesday against the Colorado Avalanche and visits the St. Louis Blues on Saturday.
Keefe said Tuesday that Marner could return as soon as the game against Colorado.
"We're unsure what his status for tomorrow is, but it's obviously a sign that it's imminent," Keefe said. "I haven't found out today on how his day went today. We'll see how his day goes tomorrow and make a decision whether it's tomorrow or the weekend."
Marner, who has 18 points (four goals, 14 assists) in 18 games, was injured against the Flyers on Nov. 9 when he got tangled up with Philadelphia forward
Carsen Twarynski
and fell awkwardly on his ankle. The team said initially that he was expected to be out a minimum of four weeks but Marner credited the medical staff for getting him to a position where he is ahead of schedule.