Essendon recruit Xavier Duursma will miss the rest of the Bombers' push to make finals with a hamstring injury.
Duursma suffered the injury late in Sunday's dramatic one-point win over Fremantle, with scans on Monday confirming the winger would miss three-to-four weeks.
"It's unfortunate news for Xavier, who'll most likely miss the remainder of our home-and-away campaign," Bombers football boss Daniel McPherson said in a statement.
"He'll begin his rehab program this week and we're hopeful it won't be the last we see of him on-field this season."
Duursma, 24, who dealt with a quad strain earlier in the season, has played 15 games for Essendon after crossing from Port Adelaide at the end of last year.
The Bombers sit two points outside the eight with three games - against Gold Coast, Sydney and Brisbane - to go.
Collingwood premiership midfielder Tom Mitchell's wretched year on the injury front has been brought to a premature end.
Mitchell, 31, has been dealing with a left foot injury all season, battling with plantar fasciitis.
He has managed just six games for the season and none since he was substituted out of the Anzac Day clash, initially resting the injury before undergoing surgery.
The Magpies said Mitchell would turn his focus towards the pre-season.
Collingwood are already without dynamo Jordan De Goey (hamstring) for the rest of the season.
North Melbourne young gun George Wardlaw will miss a second game - Saturday's clash with West Coast in Hobart - through a delayed onset concussion.
Wardlaw was sidelined for North's win over Richmond after reporting concussion symptoms in the wake of their loss to Geelong.
The 12-day concussion protocol ruled the 20-year-old midfielder out of two games.
In total, Wardlaw will have missed four games through concussion this year.
Kangaroos defender Griffin Logue will miss the final three games as he undergoes a wrist reconstruction.