The Essendon midfielder was a late withdrawal in his team's match with the Sydney Swans on Saturday night, having suffered the injury 15 minutes into the club's final training session of the week.
Last year's best and fairest winner was participating in a kicking drill and left the field grabbing at the quad. He immediately appeared distressed about the injury's severity.
Essendon football manager Paul Hamilton confirmed to AFL.com.au on Saturday the injury was a "definite tear", and that while the club doctor was yet to properly assess the MRI scans, Zaharakis would miss at least four games.
It is a huge blow for the Bombers, particularly given the 22-year-old's recent form. After a slow start to the year he has powered back to his best, and has averaged more than 28 disposals a game in the last six weeks.
Callum Twomey is a reporter for AFL Media. Follow him on Twitter at @AFL_CalTwomey.
