The first FIA World Endurance Championship Rookie test saw former F1 star and Indy 500 champion Juan Pablo Montoya top the timesheet in the Porsche 919 Hybrid with a lap a full second quicker than the fastest race lap set by Porsche's Neel Jani in Saturday's Bahrain 6 Hours.
The Colombian driver, who was invited to the test as a guest of Porsche, has been in talks with the German manufacturer over a potential driving role with the LMP1 squad in 2016 alongside his IndyCar commitments.
If Montoya is to race for Porsche he could have a shot at becoming just the second driver in history to take the prestigious Triple Crown of Motorsport – winning the Indianapolis 500, Le Mans 24 Hours and F1 Monaco Grand Prix. Legendary driver Graham Hill is the only driver to achieve this feat.
Montoya demonstrated he felt instantly at home in the Porsche 919 Hybrid by clocking the quickest time of the day with a 1m 40.861s.
Elsewhere, GP2 driver Richie Stanaway set the best time of the test in the Audi R18 e-tron quattro with a 1m 42.134s, while his countryman Mitch Evans also set an impressive time, 1m 42.946s, in the LMP1 Porsche.
In LMP2, European F3 driver Matthew Rao top the timesheet in the #36 Signatech Alpine A405b-Nissan with a 1m 52.026s, ahead of three-time Daytona 24 hour winner Memo Rojas in the #44 AF Racing BR01 Nissan.
Strakka Racing's two test drivers, Tio Ellinas and Lewis Williamson, completed a total of 34 laps between them in the Gibson 015S Nissan before an engine problem ended their day prematurely.
Five LMGTE cars took part in the test with two Porsche Team Manthey 911 RSRs driven by Philipp Eng and Nick Catsburg, while Tequila Patron ESM's David Heinemeier-Hansson also notched up laps in the Porsche 911.
Finally, three Aston Martin Vantage V8s also ran in the test to allow the team to assess six of its drivers from its Evolution Academy. Ross Gunn, Jamie Chadwick, Matt Bell, Jody Fanin, Devon Modell and Daniel Lloyd al got their first taste of the WEC alongside Archie Hamilton, Fabian Hamprecht and Salman Rashid Al Khalifa.