North Melbourne has focused on the first three and a half quarters of its win over Geelong to build its confidence ahead of Friday night's preliminary final against the Sydney Swans.

The Kangaroos were 32 points ahead of Geelong at the 14-minute of the last quarter before falling in a hole to concede the final four goals. They hung on to win the game by a goal.

Midfielder Sam Gibson – who had 35 disposals to be one of the Roos' best on the night – said the team was not dwelling on those final moments, preferring to take heart from the football it played in order to set up the lead.

"We can't get too carried away with a poor patch, and let that take away from the fact that for three and half quarters we played probably the best footy we played in the last three to five years," Gibson told AFL.com.au.

Gibson was instrumental in setting up the lead, gathering seven disposals in the first five minutes and 15 touches in the first quarter. He had seven score involvements for the game.

He was self-deprecating about his performance against the Cats but admitted it was always nice to get a touch early in a final.

"Sometimes you're lucky and the ball falls in your arms," Gibson said.

The 28-year-old, who made his debut in 2012, said he carried fewer nerves into the semi-final than the elimination final against Essendon, and the team's good start probably reflected the benefit of that experience.

Gibson leads the competition in uncontested possessions and is also in the AFL's top 10 disposal winners for the season. His game is based on his endurance and he expects to run another 15 to 16 kilometres on Friday night at ANZ Stadium when the Roos face the Swans.

"You can't ever worry about blowing up. You go as hard as you can for as long as you can. I am lucky that I can outlast most blokes," Gibson said.

Having outlasted both Essendon and Geelong in the first two weeks of the finals, North Melbourne goes into the preliminary final with confidence.
And Gibson, who was working as an engineer just three years ago, is not taking a second for granted.

"There are moments when you are standing there for the national anthem in front of 80,000 people and you sort of have to pinch yourself and think ‘how did this happen?’" he said.

"Three years ago I was slaving away in the office. It's nice every now and again to reflect."