Kelly had led for a day and a half until Jennings, in his WRC Subaru Impreza, made a charge for the lead taking ten stage wins to overcome earlier mechanical problems and a 40 second penalty.
Closing the gap on Kelly, Jennings finally took the lead on stage eight. By the time he started the final stage the Kesh driver had a comfortable 48 second lead. Then disaster struck when, within sight of victory, the Subaru caught fire sending his dreams of the Ulster Rally hat trick of wins up in smoke. Driver and co-driver are fine but the same can't be said for the car.
Jennings' retirement left the way clear for Kelly's first Ulster Rally win and a first Irish Tarmac Championship title.
It's double glory for the Donegal Town man, who a number of weeks ago wrapped up the National Championship title.
On Sunday Sport Donagh spoke with Oisin Kelly.