Formula One world championship leader Lewis Hamilton struck the first blow over his Mercedes teammate and only title rival Nico Rosberg in Friday’s opening free practice ahead of Sunday’s decisive Abu Dhabi Grand Prix.

On a hot day of blue skies and a track temperature of 44 degrees, with an air temperature of 28 degrees at the Yas Marina circuit, the two Mercedes men were a class apart from the rest of the field as they began preparations for their ‘double jeopardy’ duel in the desert.

Hamilton clocked a best lap of one minute and 43.476 seconds to finish quickest by 0.133 seconds ahead of Rosberg, the pair finishing the session more than 1.7 seconds clear of the Ferrari of Fernando Alonso, in his last race weekend with the Italian team.

With just Sunday’s race remaining, Hamilton holds a 17-point lead in the title race and must finish second, if Rosberg wins, to take the title.

Rosberg, in turn, must finish 18 points ahead of his teammate to take his first title, a situation that requires him to win or finish second and then hope for Hamilton to suffer a setback.

Alonso’s successor at Ferrari, four-time champion Sebastian Vettel, was fourth quickest as he began his final Grand Prix with Red Bull, back at the track where they began their cycle of success in 2010.

Behind the outgoing champion, his current Red Bull teammate Daniel Ricciardo was fifth fastest ahead of Frenchman Jean-Eric Vergne and his Toro Rosso teammate Daniil Kvyat, who will join Ricciardo at Red Bull next year.

Valtteri Bottas was eight fastest for Williams, his team unable to produce their expected pace due to bodywork problems that left them busy with alterations and repairs throughout the session.

His teammate Felipe Massa managed only seven laps to Bottas’ eight and was down in 13th.

Sergio Perez was ninth ahead of his Force India teammate Nico Hulkenberg.

The two McLarens of Jenson Button, whose future is the subject of much speculation, and Kevin Magnussen, were 17th and 11th respectively on a day when 20 cars were involved with Caterham rejoining the fray after missing the races in the United States and Brazil.

That meant Briton Will Stevens made his Formula One debut, in a Caterham, winding up in 20th place behind teammate Kamui Kobayashi, who was 18th and Adderley Fong, of Hong Kong, driving for Sauber.