The hosts have enjoyed an excellent second season in the league and were looking to keep their outside hopes of mounting a late top five challenge alive.
But the Sparks fell behind to an early eighth minute Josh Stanford goal for Faversham. And 11 minutes into the second half, the Kent side doubled their lead through Renford Tenyue.
Victory lifts Faversham to fourth in the table, two clear of sixth-placed Hythe Town.
Ryman League
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