North's No.6 played only the second half against Geelong but pulled up sore in the dying minutes according to GM football, Cameron Joyce.
"He experienced some tightness in his hamstring with pretty much the last kick of the game before the final siren," Joyce said.
"He'd played really well up until that point and it's very disappointing and frustrating for him, and also the club."
Garner is yet to play a match in 2018, having played a career-high 18 games in 2017.
"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," Joyce added.
After missing the AFL game against Geelong before the bye, both Jed Anderson and Jarrad Waite have been listed as "test" on the official injury update.
Waite is recovering from calf tightness, while Anderson had a hamstring complaint.
"It's a matter of assessing their functionality at training this week before we make a decision on their availability," Joyce said.
"We'll monitor them both very closely."