With Jani at the wheel in the early stages, the #2 919 Hybrid produced a laptime of 1m42.107s, 0.343s clear of its nearest rival, the #8 Audi of Loic Duval.

At the start of its final weekend in the series before exiting endurance racing, Audi put its pair of R18 e-tron quattros second and third fastest, Benoit Treluyer lapping 0.408s off the pace of Jani in the #7 car.

The #6 Toyota, which arrives in Bahrain with an outside shot at the drivers' title, was fourth quickest in the hands of Kamui Kobayashi, 0.758s slower than the car it trails by 17 points.

Completing the top six were the #1 Porsche of Timo Bernhard and the #5 Toyota of Sebastien Buemi.

Rebellion, which is taking part in its last weekend in LMP1 before stepping down to race in LMP2 next year, led sole LMP1-L class rival ByKolles by some two seconds.

The LMP2 class was led by the #36 Signatech Alpine, which wrapped up the title last time out at Shanghai, with Nicolas Lapierre establishing a benchmark of 1m50.966s.

Second-quickest was the #45 Manor Oreca of WEC returnee Roberto Merhi, a mere 0.190s slower, followed by the #26 G-Drive car (which has Rene Rast back at the wheel this weekend) driven by Alex Brundle, a further 0.058s behind.

Aston Martin on top in GTE

In GTE-Pro, Aston Martin led the way with a one-two ahead of this weekend's five-way decider.

Darren Turner put the #97 Vantage, which is out of the title race, on top with a 1m58.735 in the car he will share this weekend with Jonathan Adam, with Richie Stanaway absent.

The points-leading #95 car driven by Nicki Thiim was 0.388s back from the sister car, and three tenths up on the #77 Dempsey-Proton Porsche of Richard Lietz.

Ford, which has been hit with a 25kg Balance of Performance weight penalty after winning the last two rounds at Fuji and Shanghai, was only fifth and seventh fastest, with the two AF Corse-run Ferrari 458s taking fourth and sixth.

In GTE-Am, it was the #83 AF Corse Ferrari - which needs to score only one point this weekend to be confirmed as class champion - that led the way courtesy of a 2m01.550s lap by Emmanuel Collard.

The only car that can stop it, the #98 Aston Martin, caused a full-course yellow period after 34 minutes as Paul Dalla Lana's car had to be recovered from the gravel at Turn 1.

First practice results:

Cla	#	Drivers	Car	Class	Time	Gap
1	2	Romain Dumas Neel Jani Marc Lieb	Porsche 919 Hybrid	LMP1	1'42.107
2	8	Lucas di Grassi Loic Duval Oliver Jarvis	Audi R18	LMP1	1'42.450	0.343
3	7	Andre Lotterer Marcel Fassler Benoit Tréluyer	Audi R18	LMP1	1'42.515	0.408
4	6	Stéphane Sarrazin Kamui Kobayashi Mike Conway	Toyota TS050 Hybrid	LMP1	1'42.865	0.758
5	1	Mark Webber Timo Bernhard Brendon Hartley	Porsche 919 Hybrid	LMP1	1'42.955	0.848
6	5	Anthony Davidson Kazuki Nakajima Sébastien Buemi	Toyota TS050 Hybrid	LMP1	1'43.504	1.397
7	13	Alexandre Imperatori Dominik Kraihamer Matheo Tuscher	Rebellion R-One	LMP1	1'46.366	4.259
8	4	Simon Trummer Oliver Webb Pierre Kaffer	CLM P1/01	LMP1	1'48.308	6.201
9	36	Nicolas Lapierre Gustavo Menezes Stéphane Richelmi	Alpine A460	LMP2	1'50.966	8.859
10	45	Roberto Merhi Julien Canal Roberto Gonzalez	Oreca 05	LMP2	1'51.155	9.048
11	26	Rene Rast Roman Rusinov Alex Brundle	Oreca 05	LMP2	1'51.213	9.106
12	43	Bruno Senna Ricardo Gonzalez Filipe Albuquerque	Ligier JS P2	LMP2	1'51.581	9.474
13	30	Tom Dillmann Sean Gelael Giedo van der Garde	Ligier JS P2	LMP2	1'51.631	9.524
14	37	Vitaly Petrov Viktor Shaytar Kirill Ladygin	BR01	LMP2	1'51.885	9.778
15	35	Paul-Loup Chatin Ho-Pin Tung David Cheng	Alpine A460	LMP2	1'52.080	9.973
16	44	Richard Bradley Matthew Rao Alex Lynn	Oreca 05	LMP2	1'52.506	10.399
17	27	Maurizio Mediani Nicolas Minassian Mikhail Aleshin	BR01	LMP2	1'52.648	10.541
18	31	Pipo Derani Ryan Dalziel Chris Cumming	Ligier JS P2	LMP2	1'52.650	10.543
19	97	Darren Turner Jonathan Adam	Aston Martin Vantage V8	LMGTE PRO	1'58.735	16.628
20	95	Marco Sorensen Nicki Thiim	Aston Martin Vantage V8	LMGTE PRO	1'59.123	17.016
21	77	Richard Lietz Michael Christensen	Porsche 911 RSR (2016)	LMGTE PRO	1'59.420	17.313
22	71	Sam Bird Davide Rigon	Ferrari 488 GTE	LMGTE PRO	1'59.499	17.392
23	67	Harry Tincknell Andy Priaulx	Ford GT	LMGTE PRO	1'59.772	17.665
24	51	Gianmaria Bruni James Calado	Ferrari 488 GTE	LMGTE PRO	1'59.860	17.753
25	66	Stefan Mücke Olivier Pla	Ford GT	LMGTE PRO	2'00.371	18.264
26	83	François Perrodo Emmanuel Collard Rui Aguas	Ferrari F458 Italia	LMGTE AM	2'01.550	19.443
27	98	Pedro Lamy Paul Dalla Lana Mathias Lauda	Aston Martin Vantage V8	LMGTE AM	2'01.552	19.445
28	50	Pierre Ragues Ricky Taylor Romain Brandela	Chevrolet Corvette C7-Z06	LMGTE AM	2'01.811	19.704
29	86	Michael Wainwright Adam Carroll Ben Barker	Porsche 911 RSR	LMGTE AM	2'02.195	20.088
30	88	David Heinemeier Hansson Patrick Long Khaled Al Qubaisi	Porsche 911 RSR	LMGTE AM	2'02.237	20.130
31	78	Christian Ried Wolf Henzler Joel Camathias	Porsche 911 RSR	LMGTE AM	2'02.496	20.389