By Alan Baldwin

ABU DHABI, Oct 30 (Reuters) - McLaren shone in opening practice for the first Abu Dhabi Grand Prix on Friday with Lewis Hamilton on top in the afternoon and Heikki Kovalainen quickest after nightfall.

Britain's Jenson Button, who clinched the championship in Brazil this month to take Hamilton's crown with a race to spare, was second and third respectively at the floodlit Yas Marina circuit.

Spanish rookie Jaime Alguersuari, driving a Toro Rosso, had the honour of setting the first competitive timed lap in an incident-free debut for the track that hosts Sunday's season-ender.

McLaren's Hamilton and Brawn's Button traded fastest laps towards the end of the opening session with the outgoing champion coming out on top with a best of one minute 43.939 seconds.

Button, relishing his first race of the year with no pressure, was 0.096 slower and they were on course to repeat their earlier placings in the second session until Kovalainen beat them both.

The Finn's time in the evening, with the light falling and the waterside track lit up in preparation for the first day-to-night race, was 1:41.307 with Hamilton 0.197 slower in second place.

Both made full advantage of their KERS energy recovery system.

TRACK PRAISE

"It looks like we might be quite competitive here," said Hamilton. "Our long runs appear to be good, the car feels great and the track is great.

"It's quite interesting coming from daylight into night time, you don't notice the difference through the twilight."

Red Bull's Sebastian Vettel was third and fourth on the timesheets ahead of Brawn's Rubens Barrichello and surprising Japanese rookie Kamui Kobayashi for Toyota.

Vettel and Barrichello are fighting for second place overall in the championship.

Poland's Robert Kubica suffered a blown engine in the second session ahead of his BMW-Sauber team's last race, ending up bottom of the timesheets.

With track temperatures of 35 degrees in the first session, but dropping to 30 in the evening, and a new but dusty surface, the leading drivers sat out the first half hour.

"Obviously as the track surface is completely new, it was quite dirty, so you have to be a little careful to find your way to begin with," said Germany's Nico Rosberg, preparing for his last race for Williams.

The anti-clockwise layout also has the novel features of a hotel built across the track and a pit lane exit through a tunnel.

Team bosses heaped praise on the circuit and reported no problems for their drivers.

"It is just a stunning facility," said Ross Brawn. "A very interesting track, quite challenging.

"The pit lane is controversial but sometimes I think we are getting a bit sanitised in Formula One so a bit of extra challenge for the drivers is not necessarily such a bad thing."

McLaren's Martin Whitmarsh said everyone had been "overwhelmed by the scale and ambition" of the circuit.

"It sets standards within our sport that I think will be impossible to eclipse," he said.