The German finished the tough two-day event 5min 05.4sec clear of Keith Cronin, with series debutant Stephane Consani in third, a further 2min 08.2sec behind.
“I drove the whole weekend at 90 per cent and I think it was the right tactic. The others had problems but we had no punctures and no damage,” said Riedemann.
The results hide a heartbreaking end for Consani, who was on course for victory until an electrical problem at the end of the penultimate stage derailed his ambitions.
Consani led after the opening leg and he and Riedemann fought tooth and nail today. Although Riedemann briefly put his nose in front, Consani led by almost 15 seconds after the penultimate stage.
However, Consani’s car stopped at the finish line and refused to restart. The Frenchman and co-driver Maxime Vilmot battled to identify the problem on the roadside, finally finding a broken wire. They made emergency repairs but arrived at the final test 11 minutes late.
The time penalty dropped them to second and another four minute delay in that final test allowed Cronin through into second. The Irishman battled back after dropping nearly five minutes in yesterday’s opening stage with a puncture.
Fourth was Quentin Gilbert who was in the top three for much of yesterday before retiring when he ran out of petrol. He restarted this morning under Rally 2 regulations.
Sebastien Chardonnet completed the top five, the Frenchman losing time with a puncture yesterday and ceding more time today. However, he leaves Sardinia with a 24 point series lead over Bryan Bouffier, who finished eighth after retiring yesterday when he went off the road.
The rally was the second round of the Citroen Top Driver series and all drivers were at the wheel of DS3 R3T cars.
Click here to see the standings after the final stage.