Andre Lotterer put the #1 Audi e-tron on top by 1.3 seconds just as the chequered flag fell on the opening free practice session for the Le Mans 24 Hours on Wednesday.
Lotterer and fellow e-tron driver Tom Kristensen had engaged in a late battle for first place, with the German pipping the Dane by just over a tenth of a second 25 minutes from the end.
There was still more speed to come from the #1, though, as Lotterer demonstrated with a commanding 3m25.163s on his penultimate flying lap. Only traffic prevented an even quicker time on the next lap, as Lotterer set the best middle sector of the day before being delayed.
Although the e-trons were monopolising the leading positions by the end, both varieties of Audi and the Toyotas had also taken a number of turns on top as the four-hour session developed.
The #3 was the leading ultra in third place, 2.3s off the pace and 0.4s ahead of the sister #4 car.
Toyota's lead #7 car was fifth, 3.2s down on Audi's benchmark.
The #8 Toyota only managed five laps before developing a problem that stranded it on the Mulsanne straight, and required an engine change once it was brought back to the garage. The work should be completed in time for qualifying, but leaves the Anthony Davidson/Sebastien Buemi/Stephane Sarrazin crew very short on mileage and without a spare engine for the rest of the event.
Strakka's HPD was comfortably 'best of the rest' behind Audi and Toyota, with Danny Watts putting the car seventh overall, two seconds ahead of Pescarolo's Dome and the #12 Rebellion Lola-Toyota.
The leading few cars in the ultra-competitive LMP2 were covered by just a few tenths of a second until Ryan Dalziel moved the Starworks HPD 1.1s clear of its class rivals in the closing stages. The Jota Zytek-Nissan closed to within half a second in Sam Hancock's hands with two minutes to go, moments before Warren Hughes moved Murphy's ORECA-Nissan into third with another late improvement.
Just 0.082s covered the #24 OAK Morgan-Judd, #26 Signatech ORECA-Nissan and #45 Boutsen Ginion ORECA-Nissan in fourth, fifth and sixth places.
Aston Martin took early GTE Pro honours thanks to a 3m57.036s lap from Darren Turner. That put the car four tenths of a second ahead of the leading Luxury Ferrari, with the #74 car the top Corvette in third.
AF Corse's #51 Ferrari was fourth quickest, but will require substantial repairs before qualifying after Giancarlo Fisichella crashed at the Porsche Curves.
Fastest GTE Am car was the #79 Flying Lizards Porsche, in which Patrick Pilet lapped within 1.2s of the top GTE Pro time.
Although it lost some running with early electrical problems, the Nissan DeltaWing rejoined to set the 28th fastest time overall, ahead of six LMP2 cars. The DeltaWing lapped two seconds faster than its test day pace as it delivered a 3m43.576s, four seconds down on the LMP2 leaders.
Pos Cl Drivers Team/Car Time
1. P1 Fassler/Lotterer/Treluyer Audi e-tron 3m25.163s
2. P1 Capello/Kristensen/McNish Audi e-tron 3m26.494s
3. P1 Dumas/Duval/Gene Audi Ultra 3m27.494s
4. P1 Bonanomi/Jarvis/Rockenfeller Audi Ultra 3m27.885s
5. P1 Wurz/Lapierre/Nakajima Toyota 3m28.421s
6. P1 Davidson/Buemi/Sarrazin Toyota 3m30.162s
7. P1 Leventis/Watts/Kane Strakka HPD 3m31.651s
8. P1 Ara/Minassian/Bourdais Pescarolo Dome-Judd 3m34.035s
9. P1 Prost/Jani/Heidfeld Rebellion Lola-Toyota 3m34.154s
10. P1 Brabham/Chandhok/Dumbreck JRM HPD 3m34.641s
11. P1 Belicchi/Primat/Bleekemolen Rebellion Lola-Toyota 3m35.395s
12. P1 Montagny/Baguette/Kraihamer OAK Pescarolo-Judd 3m37.843s
13. P1 Collard/Boullion/Hall Pescarolo-Judd 3m39.656s
14. P2 Potolicchio/Dalziel/Kimber-Smith Starworks HPD-Honda 3m39.669s
15. P2 Dolan/Hancock/Kurosawa Jota Zytek-Nissan 3m40.167s
16. P2 Firth/Hughes/Hartley Murphy ORECA-Nissan 3m40.578s
17. P2 Nicolet/Lahaye/Pla OAK Morgan-Judd 3m40.727s
18. P2 Panciatici/Ragues/Rusinov Signatech ORECA-Nissan 3m40.734s
19. P2 Briere/Petersen/Nakano Boutsen ORECA-Nissan 3m40.809s
20. P2 Perez-Companc/Ayari/Kaffer Pecom ORECA-Nissan 3m41.008s
21. P2 Ordonez/Brundle/Brundle Greaves Zytek-Nissan 3m41.426s
22. P2 Martin/Charouz/Graves ADR ORECA-Nissan 3m41.660s
23. P2 Tucker/Bouchut/Diaz Level 5 HPD-Honda 3m41.825s
24. P2 Beche/Thiriet/Tinseau TDS ORECA-Nissan 3m41.832s
25. P2 Zugel/Gonzalez/Julian Greaves Zytek-Nissan 3m42.371s
26. P2 Heinemeier Hansson/Leinders/Martin OAK Morgan-Nissan 3m42.439s
27. P2 Sims/Buurman/Iannetta Status Lola-Judd 3m43.554s
28. CDNT Franchitti/Krumm/Motoyama Highcroft Delta Wing Nissan 3m43.576s
29. P2 Mailleux/Lombard/Tresson Signatech ORECA-Nissan 3m43.577s
30. P2 Frey/Hirschi/Meichtry Race Performance ORECA-Judd 3m43.751s
31. P2 Giroix/Johansson/Badey Gulf Lola-Nissan 3m45.829s
32. P2 Holzer/Schultis/Moro Kodewa Lola-Lotus 3m47.061s
33. P2 Haezebrouck/Thirion/Papin Extreme Limite Norma-Judd 3m48.380s
34. P2 Deletraz/Ihara/Rostan Gulf Lola-Nissan 3m50.666s
35. GTE P Fernandez/Mucke/Turner Aston Martin 3m57.036s
36. GTE P Makowiecki/Melo/Farnbacher Luxury Ferrari 3m57.478s
37. GTE P Gavin/Milner/Westbrook Corvette 3m57.508s
38. GTE P Fisichella/Bruni/Vilander AF Corse Ferrari 3m57.735s
39. GTE A Neiman/Pilet/Pumpelly Flying Lizard Porsche 3m58.267s
40. GTE P Lieb/Lietz/Henzler Felbermayr-Proton Porsche 3m58.543s
41. GTE A Simonsen/Nygaard/Poulsen Aston Martin 3m58.753s
42. GTE P Bergmeister/Long/Holzer Flying Lizard Porsche 3m58.930s
43. GTE P Bertolini/Beretta/Cioci AF Corse Ferrari 3m59.135s
44. GTE A Belloc/Bourret/Gibon Larbre Corvette 3m59.186s
45. GTE P Taylor/Garcia/Magnussen Corvette 3m59.480s
46. GTE P Walker/Cocker/Wills JMW Ferrari 4m00.231s
47. GTE A Armindo/Narac/Pons IMSA Porsche 4m00.800s
48. GTE A Ried/Roda/Ruberti Felbermayr-Proton Porsche 4m00.834s
49. GTE P Pilet/Curtis/Edwards/Estre IMSA Porsche 4m01.721s
50. GTE A Perazzini/Cadei/Griffin AF Corse Ferrari 4m01.985s
51. GTE A Rodrigues/Ferte/Illiano JMB Ferrari 4m02.931s
52. GTE A Ehret/Montecalvo/Jeannette Luxury Ferrari 4m03.215s
53. GTE A Kauffman/Aguas/Vickers AF-Waltrip Ferrari 4m05.952s
54. GTE A Camathias/Daniels/Palttala JWA Porsche 4m05.977s
55. GTE A Krohn/Jonsson/Rugolo Krohn Ferrari 4m06.849s
56. GTE A Bourret/Gibon/Belloc Larbre Corvette 4m07.566s