Audi completed a unique hat-trick by adding victory at the Spa 24 Hours to its triumphs in this year's twice-around-the-clock endurance classics at Le Mans and the Nurburgring.
The Phoenix Audi R8 LMS ultra shared by Frank Stippler, Rene Rast and Andrea Piccini came out on top in a close confrontation with the sister WRT car driven by Stephane Ortelli, Christopher Haase and Christopher Mies. The two Audis were only briefly split by more than a lap until the final half hour of the race.
Ortelli was running a distant second as the race entered its final hour. The team made a last-minute decision to bring in the Monegasque during a safety car period, a tactic that backfired when the car was held at the end of the pitlane and then awarded a stop-go for an unsafe pit entry.
Rast, who was making his debut in the Spa 24 Hours, said: "It was the perfect weekend. We had good race pace, good pit stops and the team took all the right decisions."
BMW Z4s finished third and fourth, the solo Vita4One entry just ahead of the Marc VDS car.
The Vita4One BMW finished on the same lap as the WRT Audi in the hands of pole winner Frank Kechele, Mathias Lauda and Greg Franchi. They fell off the lead lap early on when Lauda pitted just before the rain arrived and were never quite able to get back on terms.
The best of the cars fielded by the Belgian Marc VDS car led much of the first half of the race and was at the head of the leaderboard at six hours when the first batch of points at this double-points round of the Blancpain Endurance Series were issued. Maxime Martin, who shared the car with Bas Leinders and Markus Palttala, was consistently quickest in the wet conditions that made for a topsy-turvy first half of the event.
The BMW lost time either side of half distance, first when Leinders was hit by a Ferrari and then when Palttala, who did not drive in the first 12 hours, took a stop-go penalty awarded for exceeding track limits in free practice on Thursday.
Tom Kristensen, who was competing in the Spa 24 Hours for the first time since it became a sports car event, ended up sixth in the Phoenix Audi he shared with Andre Lotterer and Marcel Fassler. They lost time in the opening hour with a 25-minute stop to repair suspension damage caused when a McLaren MP4-12C cut across its nose entering the pitlane.
Honours in the Pro-Am class went to the AF Corse Ferrari 458 Italia driven by Andrea Bertolini, Alessandro Pierguidi, Louis Machiels and Niek Hommerson.