It was the eighth straight loss for the 4-18 Knicks.
The Knicks trailed by 43 points in the fourth quarter three nights after a 44-point loss to the Milwaukee Bucks, and Fizdale said the team's effort was "sickening."
Last month, ESPN's Adrian Wojnarowski and Malika Andrews reported that league sources said Knicks president Steve Mills had started laying the internal groundwork for Fizdale's eventual firing.
After Thursday's loss, Fizdale was asked if he was worried New York's struggles would be blamed on him.
"I don't care about all of that, I don't even think about that really," Fizdale said.
The Knicks trailed 50-44 before the Nuggets went on a 17-1 run to take a 64-45 halftime lead.
Last month, Mills and general manager Scott Perry held an impromptu news conference after another loss to make their displeasure with the team's performance clear.
"Scott and I are not happy with where we are right now," Mills said. "We think the team is not performing to the level that we anticipated or we expected to perform at, and that's something that we think we collectively have to do a better job of delivering the product on the floor."
Information from The Associated Press was used in this report.