Fyvie was having a superb game before he was cynically scythed down by hatchet man Keith Lasley, who received a deserved red card for the brutal foul.
Dons fans feared the worst after seeing replays of the disgraceful assault, which looked for all the world like the Scotland Under-19 star had broken his ankle.
But the club revealed that scans on his left ankle showed ligament damage rather than the feared break.
And Fyvie is now praying that he will be fit for the Dons' Hampden semi-final meeting with Hibs on Saturday, April 14th.
The 18-year-old wrote on Twitter: "Can't really say a time scale, but won't be [fit] for a while!!! Obviously hoping for the semi!"