The DKR Lamborghini of Manuel Lauck and Christopher Haase briefly overshadowed the FIA World GT1 title fight by setting the fastest time in the opening practice session at San Luis, Argentina.

On his 2011 debut outing in the category, former Reiter Lamborghini racer Haase recorded the best lap of 2m16.681s. Title favorites Lucas Luhr and Michael Krumm were 0.308sec adrift in second place. In order to seal the drivers' crown, the JRM Nissan GT-R duo must finish within 11 points, or better, of Young Driver Aston Martin pair Stefan Mucke and Darren Turner's weekend score.

In addition, Luhr and Krumm require only three points, equivalent of a fourth place in Saturday's qualifying race, to eliminate the three other driver pairings competing for the title.

The Germans will not have been upset to witness Turner and Mucke ending the morning ninth fastest, almost one second astray of the leading Lamborghini. JR Motorsports' sister GT-R of Richard Westbrook and Peter Dumbreck claimed third.

Markus Winkelhock and Marc Basseng's All-Inkl Lamborghini took fourth place, 0.147sec ahead of the Young Driver Aston of Alex Muller and Tomas Enge.

Winkelhock and Basseng lie third in the title race, 30 points off the lead, while Muller and Enge are very much outsiders as the fifth pairing left mathematically in contention.

Christoffer Nygaard and Jonathan Hirschi was top Ford in ninth for Belgian Racing.