Lewis Hamilton was fastest in the opening practice of the Abu Dhabi Grand Prix followed by his McLaren teammate Jenson Button.
Hamilton clocked 1 minute, 43.285 seconds on the 5.6-kilometer (3.5-mile) Yas Marina circuit on Friday, 0.333 seconds quicker than Button.
Two-time Formula One champion Sebastian Vettel, who leads the drivers' championship, was third followed by the other title contender, Ferrari's Fernando Alonso. Vettel's Red Bull teammate, Mark Webber, who still has a mathematical chance to contend for the title, was fifth.
The other remaining challenger, Kimi Raikkonen of Lotus, was 10th.
The practice in dry conditions was largely uneventful though several drivers briefly left the track. Among them was seven-time world champ Michael Schumacher of Mercedes.