Five brands occupied the top five positions in this morning's test session at Spa-Francorchamps, with the #72 SMP Ferrari emerging quickest of all.
The Russian squad's best effort of 2m19.093s came within the final 10 minutes of the two-hour run and edged out the #4 HRT Mercedes-AMG, which circulated in 2m19.492s.
The #63 Orange1 FFF Racing Lamborghini was third quickest with a 2m19.857s followed by the #66 Audi Sport Team Attempto (2m19.997) and the #22 Frikadelli Porsche (2m20.129s) entries.
The session began at 10.00 local time and saw 47 of the 50 cars take to the track, which started out damp but became drier throughout. The only major incident occurred at around 10.30 when the #11 Team Parker Racing Bentley suffered a heavy front impact at turn 18. This brought out a red flag and required repairs to the barriers, but the driver emerged unhurt.
The test days will conclude with a further five hours of running this afternoon between 13.00 and 18.00. It comes just three weeks before track activity begins for the Total 24 Hours of Spa, which will be staged on 22-25 October.