TORONTO -- The Toronto Maple Leafs moved closer to their opening day roster with a round of cuts Monday, but decisions remain on the blue line.

The NHL team trimmed down to 26 by sending 15 players to the AHL Marlies, waiving six others and returning winger Carl Grundstrom back to Sweden.

The Leafs, who open the season Wednesday in Winnipeg, have to set their opening night 23-man roster Tuesday.

Among those sent down to the Marlies were defenceman Travis Dermott and forwards Miro Aaltonen, Kasperi Kapanen and Nikita Soshnikov.

Aaltonen, a 24-year-old Finn, had impressed in camp in a tight race for fourth-line centre. Veterans Dominic Moore and Eric Fehr were kept ahead of him, however.

"Even though you're the fourth-line centre, you have to play against the best centres in the league every night. Because you're penalty killing, you've got to win faceoffs, you've got to know where to stand, and you have to be safe," Leafs had coach Mike Babcock said Monday to explain Aaltonen's demotion. "If the kid's ready, he's ready. But if it's close why not try going with a veteran and (Aaltonen) can continue to develop."

Babcock added that he expects Aaltonen to play in the NHL at some point.

More moves will be needed on the blue line with 10 players remaining in camp.

The Leafs seem set with their top four on defence with Morgan Rielly and Ron Hainsey on the first pair and Jake Gardiner and Nikita Zaitsev on the second. Connor Carrick is widely seen as the fifth defenceman.

Andreas Borgman, Timothy Liljegren, Martin Marincin, Calle Rosen and veteran Roman Polak appear on the bubble.

Polak is a wild card. Returning from a gruesome leg injury sustained in the playoffs, the 31-year-old Czech is on a professional tryout and can sign with any team.

The 18-year-old Liljegren was the Leafs' first-round draft pick this summer, taken 17th overall. He can be returned to his Swedish club or sent to the Marlies.

Colin Greening, Vincent LoVerde, Chris Mueller, Kerby Rychel, Ben Smith and Garret Sparks were placed on waivers. They can be assigned to the Marlies if they clear waivers.

Toronto Maple Leafs

Goaltenders: Frederik Andersen, Curtis McElhinney.

Defencemen: Andreas Borgman, Connor Carrick, Jake Gardiner, Ron Hainsey, Timothy Liljegren, Martin Marincin, Roman Polak, Morgan Rielly, Calle Rosen, Nikita Zaitsev.

Forwards: Tyler Bozak, Connor Brown, Eric Fehr, Zach Hyman, Nazem Kadri, Leo Komarov, Josh Leivo, Patrick Marleau, Mitch Marner, Matt Martin, Auston Matthews, Dominic Moore, William Nylander, James van Riemsdyk.