"Steve made it clear he wants to stay in Philadelphia," Thun told CSN Philly. "I've seen him play. He let in three goals in Detroit, but he shut things down when he needed to. He gave Philly an opportunity to win and that is what your goalie is supposed to do."
Mason, who can become a restricted free agent next summer, is earning $1.5 million this season and should see his salary climb above $4 million on a long-term extension.
"He's under contract and the Flyers have the right to qualify him come end of June," Thun said. "If they qualify him, he has one year before unrestricted free agency. We could go to arbitration.
"Assuming he continues to play well an arbitrator could award him a pretty big number compared to where he is right now."
Thun believes Mason's performance this season is comparable to that of the Montreal Canadiens' Carey Price.
Price has a 2.00 goals-against-average and a .937 save percentage, while Mason has a 2.14 goals-against-average and a .932 save percentage.
"I think Price is a very good comparable," Thun said.
CSN Philly notes that Mason won't get the same six-year, $39 million deal that Price received when he signed his deal, but a salary of at least $4 million, per year, seems reasonable.