North suffered a deflating loss to the previously winless Richmond on the weekend, while the Magpies were defeated in the last minute of their Anzac Day blockbuster against Essendon.
Both sides have registered two wins for the season, with Collingwood clinging to eighth position on percentage and North Melbourne sitting at 12th on the ladder.
Petrie, 26, said the weekend's results had made for a must-win clash on Friday night.
"I'm sure they're disappointed. We are too, so it makes for a pretty good game on Friday night," he said.
"It's always a good time to play Collingwood. You get a big crowd and a good atmosphere for a game of footy, and I know the guys will be up this week for that game."
The Kangaroos lost their captain Brent Harvey for up to three months on Saturday night with an elbow injury, and improving defender Lachie Hansen for four to six weeks with a hamstring.
But Petrie said panic had not set in at Arden Street, with September action still firmly in the club’s plans.
"We're only five rounds in and we're on the wrong side of the ledger at the moment, but the comp is very close and finals are still a big thing for us," he said.
"We don't feel like our backs are against the wall at this minute.
"We're only five games in and yes, we're two wins, three losses, but there is still a long way to go."
Young gun Ben Warren, who debuted two weeks ago against Essendon and made a solid contribution in both his recent senior appearances, said the players believed there was enough leadership among their ranks to cover the absence of Harvey.
"We've got plenty of veterans and players who have played as leaders with a lot of experience," he said.
"We've got good leaders in our leadership group who probably could have been up there for captaincy, so we're not worried."
Warren, 20, was hoping to hold his spot for the third consecutive week and get his first taste of the Friday night big stage this round.
"I'd love to play this week. Friday night footy is one of the big spectacles now and I'd love to keep my spot," he enthused.
"There have been a few injuries so it would be an amazing game to play in against one of the biggest clubs."
