Important North Melbourne midfielder Finn O’Sullivan is set to miss his side’s two-game swing in WA to take on Fremantle and West Coast after suffering a concussion.

On Wednesday, the Kangaroos revealed the 20-year-old — who has emerged as one of the competition’s premier taggers this season — had entered the AFL’s health and safety protocols after copping a knock at training.

He will be sidelined for at least 12 days, meaning he will not feature against Fremantle at Hands Oval on Saturday or his side’s clash with West Coast at Optus Stadium next week.

Later in the day, Channel Seven’s Ryan Daniels revealed Tristan Xerri — who has a history with concussion — was the other player involved in the clash of heads that left O’Sullivan concussed, but the star ruckman was able to complete the session.

Taken with the second selection of the 2024 national draft, O’Sullivan has earned acclaim for his performances opposed to some of the AFL’s best midfielders this season.

He kept Zach Merrett to only 10 disposals — the Essendon superstar’s lowest tally in more than six years — in his side’s win over the Bombers in round three, which came after he had started the season with a fine job on Port Adelaide star Zak Butters.

O’Sullivan spent time opposed to Harley Reid in North Melbourne’s first hit-out against the Eagles in round two, but the rising West Coast superstar was able to lead his side to their first win of the year with a 30-disposal effort.

Opposition coaches have often opted to invest time into Caleb Serong in games against Fremantle, but the vice-captain will remain sidelined by a calf injury for their first game for premiership points in the South West.

O’Sullivan’s absence may open up a place for York product Zac Fisher to play his first AFL game of the season for the Kangaroos.

Fisher has been in fine form for in the VFL, having won 22 disposals and kicked three goals in his most recent hit-out against Gold Coast’s reserves.