Taylor Garner could face another complete season on the sidelines for North Melbourne, after being hurt on his VFL return.
The midfielder/forward has been plagued by left hamstring problems since 2014, when he missed the whole season.
The 24-year-old hoped last year was a turning point in his fortunes, when he played a career-high 18 games.
We'll take as much time as required to ensure that he can get over this hurdle.Cameron Joyce
But the hamstring issues which affected him throughout the 2015 and 2016 campaigns, have hit him again and he may not return to the AFL this season.
The Kangaroo, who has played 34 AFL games overall, was hurt right at the end of his VFL outing against Geelong at GMHBA stadium last week.
North football boss Cameron Joyce said: "He experienced some tightness in his hamstring with pretty much the last kick of the game before the final siren. He'd played really well up until that point and it's very disappointing and frustrating for him, and also the club.
"We'll take as much time as required to ensure that he can get over this hurdle and return to football for a long, sustained run."
Garner, who was recruited in the 2012 AFL Draft, was also nursed through the pre-season with hip and groin injuries.
North hope to have Jed Anderson (hamstring) and Jarrad Waite (calf) back for their meeting with Western Bulldogs at Etihad Stadium on Saturday.
Waite was a late withdrawal before last weekend's 54-point victory against Brisbane, while Anderson has missed the past two games.
The pair will face fitness tests later in the week, with Joyce saying: "It's a matter of assessing their functionality at training this week before we make a decision on their availability."
The Kangaroos should have captain Jack Ziebell back after he cut his knees running into the LED fence at GMHBA Stadium against Geelong a fortnight ago.
North Melbourne are 27/100 to beat Western Bulldogs, who are 3/1.
The Kangaroos are 93/100 conceding a 32.5-points start.
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