The Cowboys are suffering a crisis of confidence just three weeks into the 2015 season.

Struggling Cowboys to lift intensity

Cowboys coach Paul Green is hoping a more intense week of training is the tonic to turn around an underwhelming start to the NRL Telstra Premiership season.

Both Green and co-captain Johnathan Thurston have put the team's slow start down a lack of confidence after showing flashes of brilliance throughout the first three rounds followed by periods of "turnstile" defence, as Thurston said after Friday night's loss to the Broncos.

In a fifteen-minute stretch against the Broncos, North Queensland conceded more points (20) than Brisbane had scored in their previous two games combined (16).

Going into Round 4 sitting in last on the premiership ladder, Green said this week was all about preparing the right way to keep their heads in the game for the full 80 minutes ahead of Monday's clash with Melbourne.

"One thing that's essential ingredient in confidence is your preparation. You need to prepare well so come game day when you look back on the week you've had, you've ticked all the boxes that you need to," Green said.

"You need to control the things that are controllable and make sure you're doing all those things well. It's underpinned by a little bit of hard work.

"The other thing is you don't forget how to play footy. You go back six months ago, at the back end of last year, and it was largely the same squad and same team.

"It's about reminding them of the good stuff they can do and being prepared to fight a little bit harder when the game is on the line."

In a positive for the club, winger Antonio Winterstein returned to training on Monday after a leave of absence and will slot in beside long-term foil Kane Linnett against the Storm.

As the club's leading try-scorer last season (15), Winterstein's inclusion provides some much-needed experience on the left wing, while Kyle Feldt drops back to the Intrust Super Cup after a two-try outing in Brisbane.

"They've certainly played a lot of footy together, Kane (Linnett) and 'Tones (Winterstein). He's a pro, 'Tones, he's got plenty of experience back there and it's probably what we need," Green said.

Linnett added: "I'm pretty close with 'Tones and I've been trying to talk to him the last couple of weeks, but he's been around his family and it has been a tough time. I think he was just excited to just get back into training and get back into the routine of a normal life.

"For me personally, I've been with him for a few years now on my edge. Having him outside me and knowing what he's been through the last couple of weeks will definitely be a boost."

Things do not get any easier for North Queensland after facing an in-form Storm on Monday, with away games against the first-placed Panthers and second-placed Souths in Rounds 5 and 6.