Audi's Le Mans-winning hybrid set the pace in the opening free practice session for the latest round of the FIA World Endurance Championship, the Silverstone 6 Hours.
The R18 e-tron Quattro driven by Marcel Fassler, Benoit Treluyer and Andre Lotterer, emerged fastest in the session with a 1m45.777s lap, the best of the 43 the car completed.
Toyota's TS030 Hybrid of Alex Wurz, Nicolas Lapierre and Kazuki Nakajima, which had run so well at Le Mans in June for the opening quarter of the race, was second fastest, just 0.233 seconds slower than the pacesetter.
Third was the diesel Audi R18 ultra of Tom Kristensen/Allan McNish while the best of the privateer LMP1 entrants was the JRM HPD of David Brabham/Peter Dumbreck/Karun Chandhok, less than a second off the pace.
OAK Racing's Morgan-Judd was fastest in LMP2, just two thousandths of a second ahead of the Greaves Motorsport Zytek-Nissan that features Martin and Alex Brundle in the line-up.
AF Corse's leading Ferrari was the class of the field in GTE Pro in the hands of Giancarlo Fisichella/Gianmaria Bruni and headed the sister car of Andrea Bertolini/Olivier Beretta.
The Felbermayr-Proton Porsche was third with Aston Martin Racing's Vantage V8 next up.
Irishman Matt Griffin was fastest in GTE Am in the AF Corse Ferrari he shares with Piergiusepe Perrazzini and Marco Cioci.
Second practice takes place on Friday evening.
Pos Cl Drivers Team/Car Time 1. P1 Fassler/Lotterer/Treluyer Audi e-tron 1m45.777s 2. P1 Wurz/Lapierre/Nakajima Toyota 1m46.010s 3. P1 Kristensen/McNish Audi ultra 1m46.138s 4. P1 Brabham/Chandhok/Dumbreck JRM HPD 1m46.491s 5. P1 Leventis/Watts/Kane Strakka HPD 1m47.609s 6. P1 Prost/Jani Rebellion Lola-Toyota 1m48.095s 7. P1 Belicchi/Primat Rebellion Lola-Toyota 1m48.188s 8. P2 Heinemeier Hansson/Baguette/Kraihamer OAK Morgan-Nissan 1m51.561s 9. P2 Ordonez/Brundle/Brundle Greaves Zytek-Nissan 1m51.563s 10. P2 Nicolet/Lahaye/Pla OAK Morgan-Nissan 1m51.910s 11. P2 Panciatici/Ragues/Rusinov Signatech ORECA-Nissan 1m52.148s 12. P2 Perez Companc/Ayari/Kaffer Pecom ORECA-Nissan 1m52.235s 13. P2 Firth/Hughes/Hartley Murphy ORECA-Nissan 1m52.240s 14. P2 Martin/Charouz/Graves ADR-Delta ORECA-Nissan 1m52.302s 15. P2 Dolan/Hancock/Minassian Jota Zytek-Nissan 1m52.627s 16. P2 Potolicchio/Dalziel/Sarrazin Starworks HPD 1m53.065s 17. P2 Mailleux/Lombard/Tresson Signatech ORECA-Nissan 1m54.063s 18. P2 Weeda/Rossiter/Liuzzi Lola-Lotus 1m54.342s 19. P2 Sims/Jousse/Jousse Status Lola-Judd 1m54.379s 20. P2 Giroix/Ihara/Deletraz Gulf Lola-Nissan 1m56.833s 21. P2 Holzer/Schultis/Albers Lola-Lotus 1m57.467s 22. GTE P Fisichella/Bruni AF Ferrari 2m02.757s 23. GTE P Bertolini/Beretta AF Ferrari 2m03.115s 24. GTE P Lieb/Lietz Felbermayr Porsche 2m03.166s 25. GTE P Fernandez/Mucke/Turner Aston Martin 2m03.440s 26. GTE P Walker/Cocker JMW Ferrari 2m03.786s 27. GTE A Perazzini/Cioci/Griffin AF Ferrari 2m04.080s 28. GTE A Goethe/Hall Aston Martin 2m04.136s 29. GTE A Krohn/Jonsson/Rugolo Krohn Ferrari 2m04.493s 30. GTE A Adam/Howard/White Aston Martin 2m04.565s 31. GTE A Ried/Roda/Ruberti Felbermayr Porsche 2m04.580s 32. P2 Zugel/Gonzalez/Julian Zytek-Nissan 2m05.009s 33. GTE A Bornhauser/Canal/Rees Larbre Corvette 2m05.343s 34. GTE A Camathias/Palttala/Daniels JWA Porsche 2m06.654s 35. GTE A Belloc/Bourret/Gibon Larbre Corvette 2m07.560s