Former Newcastle and international representative Adam MacDougall has delivered an extraordinary spray towards outgoing Knights owner Nathan Tinkler, labelling the ex-mining billionaire "arrogant" and "not a very nice person" who had left the club in far worse shape.

The reign of Tinkler and the Hunter Sports Group came to a close on Friday with reports Newcastle has been left with debt of as much as $20 million and the future of some players and master coach Wayne Bennett under a cloud.

MacDougall, nicknamed "Mad Dog", who played in the Knights' premiership teams in 1997 and 2001, took aim at Tinkler on Sunday.

"Nobody knows how much debt it's left in," he said on Channel Nine. "There is a disconnect between the community and the club now. The media up there, he doesn't even allow the club and the players to speak to them. It was a team that was based around the community. They have nothing to do with the community any more.

"He's come in ... he's an arrogant ... I'm not even going to go into what I think of him personally, but my discussions with him made me want to have nothing to do with the club.

"He's not a very nice person. The way that he speaks about people in general, and the way that treats people. You judge someone by the way they treat somebody who can't do anything for them. The low man, the little man.

"We all know the history of him. We were warned before he came to the club about his racing history and we've seen how it all played out in the soccer [at the Newcastle Jets] with the way he sacked the Culinas and whatnot. It's never ended well anywhere he's gone and Newcastle are now going to be left with some say a massive amount of debt."

MacDougall said he doubted whether Bennett, who was contracted directly to Hunter Sports Group, would stay. "Wayne Bennett has been a great coach. But I can assure you now he's not going to be there when the money dries up," he said. "The club is in a much worse position as far as I'm concerned."