Essendon could face its must-win clash with Fremantle next week, plus its possible finals campaign, without small forward Josh Green.
Green, who has booted 17 goals this season, injured his left foot in the last quarter of the Dons' 33-point win over the Suns on Saturday night as he ran and turned to take possession of the ball.
He was taken straight to the rooms and returned to the bench soon after wearing a moon boot and on crutches.
It is believed it could be a similar injury to the fracture Green suffered in his right foot in 2016, which saw him miss around 10 weeks of football.
"That looks like it's serious," coach John Worsfold told Triple M on Sunday.
"He fractured a bone in his foot up in Brisbane a few years ago and had that pinned, and there's a possibility this is the same thing as the other foot.
"We'll get that confirmed tomorrow but it's not looking that great at this stage for him."
Meanwhile, star defender Michael Hurley, who missed yesterday's game due to a calf injury, is no certainty to return to the side next week.
"He's got to get through the hoops of showing that he's fit to go," Worsfold said.
"He's pretty bullish about it but we'll wait and see."
Essendon, who currently sit eighth with 11 wins and 10 losses following last night's win, host Fremantle at Etihad Stadium next Sunday afternoon.