"Thursday morning I thought I may be in a bit of trouble but the support staff and the doctors got me up and feeling good," Jacobs said on Monday.

"I was scared to weigh myself, actually, because I didn't need that going into a final.

"After the game I weighed myself and I was probably a good three or four kilos lighter than I usually weigh in at, but I felt fine during the game.

"But I definitely wasn't going to weigh myself during the week.

"I had a jog around on Friday, which was good to have a bit of a blowout. It was ugly at times but I was able to get up … in front of 90,000 people, the sickness didn't feel too bad."

Roos no longer 'hoping' to win finals, says ruckman

North's win set up a semi-final clash against the Sydney Swans at ANZ Stadium on Saturday night in a rematch of last year's preliminary final that ended in a 71-point victory to the Swans.

John Longmire has plenty of injury concerns heading into the clash, with Sam Reid joining star Swans Lance Franklin, Kieren Jack and Luke Parker on the sidelines.

The wounded Swans still have plenty of weapons, however, with imposing midfielder Josh Kennedy a possible target for Jacobs after his masterful 39-possession performance against Fremantle.

"There's a few possibilities but he played sensationally on the weekend, he pretty much kept them in the game at times, I'm not sure who I'm going to go to but he's definitely one (chance)," Jacobs said.

"He's a contested ball beast so he'd be another challenge.

"I haven't done the tape on him yet but hopefully I can find some way to nullify him."