The 22-year-old forward is
one of two remaining unsigned restricted free agents
, along with Anaheim Ducks forward Nick Ritchie.
"I've been asked, 'Do you want to trade him right now?' And the answer is, 'No,'" Dubas said. "Circumstances can change. But it's not in any plan or any discussion we've had that we're going to trade any of these players.
"Our goal is to have them each develop and maximize their potential here."
Nylander finished third on the Maple Leafs in points last season with 61 (20 goals, 41 assists) in 82 games.
The Maple Leafs open the season against the Montreal Canadiens at Scotiabank Arena on Wednesday (7 p.m. ET; SN, RDS, NHL.TV).
The signing of center John Tavares to a seven-year, $77 million contract July 1 brought into question the Maple Leafs' ability to keep Nylander and forwards Auston Matthews and Mitchell Marner. Matthews and Marner can each become a restricted free agent after the season. They have been eligible to sign a contract extension since July 1.
"Those discussions with their representatives are ongoing," Dubas said. "I know everybody would like everything to happen quickly, but there's a process we go through. Would we like to have had it all sorted out and done on the first day? Yes, but I don't think that's realistic.
"When you're developing your own players and your own people, and they grow up as Toronto Maple Leafs and they help your program develop, those are the types of guys you want around long term. That's just reality. That's always been our goal."
Dubas said he'd like to sign Nylander to a long-term contract.
"With any player coming off of his entry level (contract), it's always, 'Is it long term or is it bridge?'" Dubas said. "The long term is where both parties, our camp and their camp, have been focused on. Those ones are often the hardest ones to do, because they are a much bigger decision for the player and a much bigger decision for the team."
Selected by the Maple Leafs with the No. 8 pick of the 2014 NHL Draft, Nylander has 135 points (48 goals, 87 assists) in 185 NHL games. His average of 0.77 points per game is third among players selected in the 2014 draft with at least 100 NHL games, behind Boston Bruins forward David Pastrnak (0.80) and Edmonton Oilers forward Leon Draisaitl (0.77).
