In the end, it was a scintillating lap of 1m38.828s by di Grassi in the closing stages of the session that ensured the Ingolstadt marque came out on top, with Jarvis' earlier time making for an average of 1m39.207s.

That was enough to overcome the #1 Porsche, started by Timo Bernhard, taken over by Brendon Hartley and then handed back to Bernhard, by 0.264s, with Bernhard's best effort a full half-second slower than that of di Grassi.

The points-leading sister #2 919 Hybrid, shared by Neel Jani and Marc Lieb, took the third spot, 0.198s behind the #1 machine and 0.462s behind pole on average times.

Audi's second car, the #7 of Andre Lotterer and Marcel Fassler, could only manage fourth quickest, as Lotterer failed to improve on his earlier time after taking back over the car from Fassler late in the session.

Toyota locked out the third row with its pair of TS050 Hybrids, neither of which seemed to have the pace when it mattered.

The title-contending #6 machine of Kamui Kobayashi and Mike Conway, who had a time deleted for a track limits violation, was fifth, 1.015s off the pace and half a second clear of the #5 car of Anthony Davidson and Kazuki Nakajima, who were also hobbled by having an early laptime deleted.

Rebellion Racing took LMP1 privateer pole in its last race in the division, as the ByKolles failed to set a time during qualifying.

LMP2 pole went to the #26 G-Drive Oreca of Rene Rast and Roman Rusinov, whose combined efforts produced an average of 1m49.672s.

That was 0.018s up on the #36 Signatech Alpine shared by Gustavo Menezes and Stephane Richelmi, while third place went to the best of the Manor Orecas, the #44 of Alex Lynn and Matt Rao.

Aston Martin sweeps GTE classes

In GTE-Pro, it was the #95 Aston Martin car of Darren Turner and Jonathan Adam that took pole position - with both drivers incredibly setting identical laptimes of 1m56.953s.

That gave the all-British duo a margin of 0.128s over the points-leading sister #95 car of Nicki Thiim and Marco Sorensen, who need to finish in third place on Saturday to be certain of the class title.

Ferrari supplied the closest opposition to Aston Martin, with the #51 car of Gianmaria Bruni and James Calado putting in an average time 0.427s off the pace, while the best of the Fords, the #67 of Harry Tincknell and Andy Priaulx, was fourth, a further half a second back.

Pole position for the #98 Aston Martin of Pedro Lamy and Paul Dalla Lana in GTE-Am ensures that the race for title honours in that class goes on, although the #83 AF Corse squad needs only to finish on Sunday to take the crown.

Qualifying results - LMP1 and LMP2

Cla	#	Drivers	Car	Class	Time	Gap
1	8	Lucas di Grassi Loic Duval Oliver Jarvis	Audi R18	LMP1	1'39.207
2	1	Mark Webber Timo Bernhard Brendon Hartley	Porsche 919 Hybrid	LMP1	1'39.471	0.264
3	2	Romain Dumas Neel Jani Marc Lieb	Porsche 919 Hybrid	LMP1	1'39.669	0.462
4	7	Andre Lotterer Marcel Fassler Benoit Tréluyer	Audi R18	LMP1	1'39.698	0.491
5	6	Stéphane Sarrazin Kamui Kobayashi Mike Conway	Toyota TS050 Hybrid	LMP1	1'40.222	1.015
6	5	Anthony Davidson Kazuki Nakajima Sébastien Buemi	Toyota TS050 Hybrid	LMP1	1'40.776	1.569
7	13	Alexandre Imperatori Dominik Kraihamer Matheo Tuscher	Rebellion R-One	LMP1	1'45.091	5.884
8	26	Roman Rusinov René Rast Alex Brundle	Oreca 05	LMP2	1'49.672	10.465
9	36	Nicolas Lapierre Gustavo Menezes Stéphane Richelmi	Alpine A460	LMP2	1'49.690	10.483
10	44	Richard Bradley Matthew Rao Alex Lynn	Oreca 05	LMP2	1'50.034	10.827
11	43	Bruno Senna Ricardo Gonzalez Filipe Albuquerque	Ligier JS P2	LMP2	1'50.410	11.203
12	30	Giedo van der Garde Tom Dillmann Sean Gelael	Ligier JS P2	LMP2	1'50.685	11.478
13	45	Roberto Merhi Julien Canal Roberto Gonzalez	Oreca 05	LMP2	1'50.800	11.593
14	31	Pipo Derani Ryan Dalziel Chris Cumming	Ligier JS P2	LMP2	1'51.071	11.864
15	35	Paul-Loup Chatin Ho-Pin Tung David Cheng	Alpine A460	LMP2	1'51.185	11.978
16	27	Maurizio Mediani Nicolas Minassian Mikhail Aleshin	BR01	LMP2	1'51.427	12.220
17	37	Vitaly Petrov Viktor Shaytar Kirill Ladygin	BR01	LMP2	1'51.475	12.268

Qualifying results - GTE

Cla	#	Drivers	Car	Class	Avg Time	Gap
1	97	Darren Turner Jonathan Adam	Aston Martin Vantage V8	LMGTE PRO	1'56.953
2	95	Marco Sorensen Nicki Thiim	Aston Martin Vantage V8	LMGTE PRO	1'57.081	0.128
3	51	Gianmaria Bruni James Calado	Ferrari 488 GTE	LMGTE PRO	1'57.380	0.427
4	67	Harry Tincknell Andy Priaulx	Ford GT	LMGTE PRO	1'57.891	0.938
5	71	Sam Bird Davide Rigon	Ferrari 488 GTE	LMGTE PRO	1'58.201	1.248
6	66	Stefan Mücke Olivier Pla	Ford GT	LMGTE PRO	1'58.504	1.551
7	77	Richard Lietz Michael Christensen	Porsche 911 RSR (2016)	LMGTE PRO	1'58.882	1.929
8	98	Pedro Lamy Paul Dalla Lana Mathias Lauda	Aston Martin Vantage V8	LMGTE AM	1'59.879	2.926
9	83	François Perrodo Emmanuel Collard Rui Aguas	Ferrari F458 Italia	LMGTE AM	2'00.227	3.274
10	50	Pierre Ragues Ricky Taylor Romain Brandela	Chevrolet Corvette C7-Z06	LMGTE AM	2'00.938	3.985
11	86	Michael Wainwright Adam Carroll Ben Barker	Porsche 911 RSR	LMGTE AM	2'02.112	5.159
12	78	Christian Ried Wolf Henzler Joel Camathias	Porsche 911 RSR	LMGTE AM	2'39.576	42.623