Singapore : Nico Rosberg led the way in an eventful final practice session Saturday for the Singapore Grand Prix as Lewis Hamilton again struggled and a giant monitor lizard startled Max Verstappen.
Rosberg's quickest lap of 1 minute 44.352 seconds will give Mercedes hope that they have exorcised the demons of a year ago when they could only qualify fifth and sixth fastest.
But they did not have it all their own way as teammate Hamilton's woes continued for the second day running and Red Bull and Ferrari closed in.
Red Bull's Verstappen was second fastest, just 0.059 sec behind Rosberg, having regained his composure after a large reptile ran across the track in front of him.
"There's a giant lizard on the track!" shouted Verstappen over team radio as a monitor lizard in excess of a metre long meandered across the Marina Bay street circuit.
Ferrari's Kimi Raikkonen was third, half a second adrift of Rosberg, with Red Bull's Daniel Ricciardo only a 10th of a second behind the Finnish driver, despite being baulked by a back marker on his fastest run.
Last year's winner, Sebastian Vettel, was unhappy with his Ferrari's set-up, at one point telling his team he could not control the rear of the car and felt "like a passenger" as he slumped to fifth place, three-quarters of a second off Rosberg's pace.
Meanwhile Hamilton, who leads Rosberg by just two points in the world championship standings, twice locked up his ultrasoft tyres in clouds of smoke at turn seven and skidded down the escape road.
Hamilton's best time came on the slower supersoft tyres, but was only good enough for eighth place, 1.454 sec slower than Rosberg and trailing behind the Force India of Nico Hulkenberg and the Toro Rosso of Daniil Kvyat.
It means Hamilton, who had a hydraulic problem which curtailed his Friday running, has yet to complete a flying lap on the quickest ultrasoft tyres before the crucial qualifying session later Saturday.
Six of the eight Singapore Grands Prix since the race's inception have been won by the man on pole position.
It promises to be a three-team fight between Mercedes, Red Bull and Ferrari for grid honours -- so important when the tight characteristics of the city centre circuit make overtaking notoriously difficult.
But Red Bull team principal Christian Horner played down his team's chances of taking pole position on a track which suits their car's high mechanical grip.
"I doubt it," he told the BBC. "Lewis locked his front and flat-spotted so we didn't see his true pace and Rosberg looks like he has 0.1-0.2secs in there but we will see what happens."