North Melbourne midfielder Jack Ziebell says his side must improve in all areas or risk being “left behind” in 2015.

The vice-captain has been impressed with his teammates’ determination this pre-season, with the entire playing group desperate to take their football to another level.

“There were a few areas in big games last year that let us down and definitely our consistency across four quarters – we were a little bit up-and-down,” Ziebell told Channel 9 on Wednesday.

“We’re working on that and making sure we put four quarters of consistent football together and if we do that, we’re going to be a pretty hard team to beat.

“The rest of the competition is going to improve and if we don’t, we’re going to get left behind.”

Ziebell has returned to full training following post-season shoulder surgery and expects to be fit and ready to run out for the NAB Challenge.

The 23-year-old said senior coach Brad Scott was ensuring the players are at their best as games approach.

“He (Scott) understands where we need to be and he’s driving us really hard. That’s what you want from your senior coach – to lead the way in that area,” Ziebell said.

“We’re looking forward to getting out there in the NAB Challenge in a couple of weeks time and strutting our stuff and start playing our footy.”

Ziebell, now in his seventh pre-season at North, said the club’s loss to Sydney in the Preliminary Final had been a “kick in the guts” but every player was now focused on 2015.

“A solid and good pre-season can really set you up for a positive year and I think that’s where we are at.”