Michael Christensen leads the Total 24 Hours of Spa in the No. 117 KÜS Team75 Bernhard Porsche 911 GT3 R with three hours to go, but the factory supported entry is still due a pitstop.
At least five cars are still in with a shot of the overall win in the Belgian Endurance classic, with the order changing as pit stops progress.
Christensen, who shares the Porsche with fellow factory drivers Laurens Vanthoor and Kevin Estre, currently holds a 36-second lead on the No. 2 Audi Sport Team WRT Audi R8 LMS in the hands of Frédéric Vervisch, which is also off-sequence.
The effective leader is still the No. 90 AKKA ASP Mercedes-AMG GT3 of Raffaele Marciello, closely followed by the No. 25 Audi Sport Team Sainteloc Audi and No. 1 Audi Sport Team WRT Audi.
It is expected the Porsche will be 50 seconds down after its next stop.
Mortara almost crashed out of the lead at the top of Raidillon in the No. 90 Mercedes, after light contact with a Cup class Porsche that sent it into a spin.
The Italian driver managed to keep his car out of the barriers and only lost around 15 seconds with the incident.
BMW is now out of the lead battle, despite a lengthy pit stop for the No. 98 ROWE Racing BMW M6 GT3 to fix a technical issue, dropping the car from P7 to P11.