Leijer had only just made it onto the ground during injury time in Saturday night's 3-1 win over Central Coast when the 27-year-old clashed with Mariners forward Matt Simon.
After visiting a specialist in Melbourne on Tuesday morning, it was revealed Leijer had sustained a fractured eye-socket, a fractured cheekbone, as well as a fracture to his nose.
The injuries continue a frustrating campaign for Leijer, who's season has been interrupted by injuries and suspension.
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