The sort of defensive play Adam O'Brien has based most of his coaching principles around over the past four and a half months. A tackle, that in the context of the game, meant so little and yet so much.

It came with less than two minutes left in Saturday's game against the Warriors. The Knights were up 20-0. The game was in the bag and had been for some time when Warriors fullback Roger Tuivasa-Sheck took advantage of some broken field play after a ball went lose close to the Knights line and looked certain to score.

But as he surged for the try-line, the Warriors skipper was brilliantly cut down by a flying Edrick Lee. The Knights winger, sensing his side was struggling to scramble in time, came from the clouds to plug the gap and stop the try.

It reeked of effort. Almost 79 minutes down, Lee could easily have stayed out on his left wing, allowed Tuivasa-Sheck to waltz over and nothing would have been said. No fingers would have been pointed.

What it showed was a tougher mindset, a mindset the side carried right through the 80 minutes in their season opener. A mindset and attitude to defence far removed from that of the mentally fragile Knights of last season.

Mitch Barnett's second half bell-ringer on Warriors centre David Fusitu'a was another prime example of it. O'Brien has been talking ad nauseam about effort and defensive resilience since he first lobbed in Newcastle.

On the strength of Saturday's performance, his players have clearly been listening. Not surprisingly, the rookie coach was proud of his squad following his winning NRL debut.

"I'm pleased with our defence, I'm pleased with the zero, I'm pleased with the resolve on the try-line," O'Brien said. "The coach in me is saying we've still got work to do ... but at the same time, I can only be proud of them. I asked for effort in defence and that's what I got so I've got to be happy with them tonight.

"Edrick's tackle at the end probably typified it for me. He doesn't put himself in that frame, we still win, but that's not the attitude of this group. That's not what we want. We want to make sure we're putting ourselves in the frame every time, no matter what the scoreboard says."

Warriors coach Stephen Kearney was just as impressed with the Knights' defensive resolve.

"We got beat up today," he said. "I thought they did a good job defensively the Knights. We couldn't get any traction with the footy."

To their credit, the players weren't getting carried away on the strength of one win and with a huge shadow hanging over the NRL because of the coronavirus.

"It's a great way to start and I'm proud of our efforts, but there's always room to improve," Kalyn Ponga said.

"And despite everything that's happening in the world, to have 10,000 out there in the rain, that's pretty memorable. We love our fans, and to get that sort of turn-out - it's huge."

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