Donnan won the Grand Final ahead of Ryan Farquhar although the Dungannon rider did have the consolation of claiming victory in the 600cc race where he edged out Davy Morgan and Victor Gilmore.
But Geraghty clinched the Daily Telegraph Leading Rider award when he recorded his fifth victory, winning the final race of the meeting on Spirit Leader.
The awkwardness peaked in Thursday's final mountain stage when Froome repeatedly turned and held up for Wiggins as another rider went on to win the stage.
The 31-year-old Garmin rider snatched the pink jersey from Spain's Joaquim Rodriguez on the final time trial stage in Milan, forging a winning margin of just 16 seconds after 21 stages.