Lewis Hamilton reeled off a track record lap as he topped the times for Mercedes ahead of Sebastian Vettel's Ferrari in Friday's twilight second free practice for this weekend's Abu Dhabi Grand Prix.
The newly-crowned four-time world champion Hamilton clocked a best lap of one minute and 37.877 seconds to outpace German Vettel, also a four-time champion, by one-tenth of a second in a session that began in sunlight and finished after dark.
Australian Daniel Ricciardo was third-quickest for Red Bull ahead of the Finns Kimi Raikkonen of Ferrari and Valtteri Bottas in the second Mercedes. Dutchman Max Verstappen was sixth for Red Bull.
It was a tightly-contested session in which Raikkonen and Bottas also topped the times and Hamilton and Vettel traded fastest laps, suggesting overall that all three leading teams are in with a chance to win Sunday's day-night race at the spectacular Yas Marina circuit.
Hamilton, running on ultra-soft tyres in the closing stages, gave a withering assessment of the Pirelli compound. "This is the worst tyre I've ever driven," he said.
His pithy comment provided one of the most dramatic moments in an otherwise pedestrian session as the teams prepared ahead of Saturday's qualifying.
Using a fresh and updated Mercedes engine, Hamilton is likely to start as favourite for the final race of the season if he can translate his practice pace into qualifying and race performance.
Behind the top six, the Force India cars of Mexican Sergio Perez and Frenchman Esteban Ocon led the way in seventh and eighth ahead of German Nico Hulkenberg of Renault and two-time champion Spaniard Fernando Alonso of McLaren Honda.
Subscribe to Arabian Business' newsletter to receive the latest breaking news and business stories in Dubai,the UAE and the GCC straight to your inbox.