Paul Gallen admits St George Illawarra will make it a long night for Cronulla on Monday if they repeat last week's hapless NRL display against Canberra.

The Sharks were demolished 40-12 by the Raiders in last Sunday's opening round, a performance the Sharks skipper compared to a reserve grade side.

However, the NSW and Test backrower believes his Sharks are a better side than their performance suggested.

"It was a real ordinary game, we probably started okay, but you've got to play for 80 minutes these days and we didn't do that, but it's only round one," Gallen said.

"We've put it behind us and we've got a big challenge this week playing the premiers, and everyone's going to lift to play them. It's a local derby and form goes out the window a little bit and we're keen to play.

"We were absolutely ordinary last week, we would've been lucky to beat a NSW Cup side to be honest, so we've got a lot of improvement in us."

Gallen revealed coach Shane Flanagan, in his first full season at the helm, was furious that the the team went away from his game plan, but denied the players had fallen back into the bad habits that have plagued them for two years.

"The way we trained the past couple of weeks didn't reflect the way we played, and that was the most disappointing thing - we have to put in the game what we're doing in practice," he said.

"We spoke about bad habits, and when you're down by 30 points and you try to play catch-up footy you're going to start throwing balls out the back.

"Everyone does it, but we probably just don't have the cohesion at the moment to be able to do that.

"So we have to get a game plan and stick to it, and that was the most upsetting thing for the coaches, we came up with a good game plan that we thought would work well and we didn't stick to it."

Sharks enforcer Jeremy Smith will face the Dragons for the first time since helping the joint-venture lift their first premiership in October.

The New Zealand star has solidified an already powerful forward pack but Gallen said there has been no need to ask him for a heads-up about his former team.

"I don't think you need any inside tips on the Dragons, you pretty much know what's coming at you, the hard thing is stopping it," Gallen said.

"They haven't changed too much over the past couple of years, just the big boys roll forward, they complete their sets and don't give away penalties.

"It's a very simple game-plan but it works."

Brought to you by AAP © 2024 AAP