SINGAPORE (AP) Mercedes driver Lewis Hamilton set the fastest time in practice for the Singapore Grand Prix on Friday, while teammate and title rival Nico Rosberg and defending champion Sebastian Vettel both had setbacks.
Hamilton's best time of 1 minute, 47.490 seconds at the Marina Bay circuit was a tenth of a second faster than Ferrari's Fernando Alonso, who was fastest in the morning session.
''Pole here has always been very important,'' Hamilton said. ''Being up at the front will be crucial and that's obviously my target for qualifying tomorrow.
''Nico looks very quick, as do the Ferraris and the Red Bulls, but I'm feeling good this weekend and I'm focused on the job.''
Rosberg's hopes of surpassing his teammate were ruined when his lap on fresh super-soft tires had to be aborted due to a red flag caused by Pastor Maldonado's heavy collision with a barrier. Rosberg was only 13th fastest.
''Although I didn't get the second part of that lap, though, in the first part the car felt great,'' Rosberg said. ''It's generally a great challenge driving here. This is one of the most difficult tracks out there but to fight through all the curves and bumps ... is a great feeling.''
Vettel came out for only the last eight minutes of the second session after an engine failure in his Red Bull at the end of the first. The German, who has won the past three Singapore races, still had enough time to vault up to fifth on the timesheets.
''I was not able to get the best out of the tires straight away,'' Vettel said. ''But overall I am pretty happy and I am sure we can improve the car. We should be in a good place tomorrow.''
While the Renault engine that failed was one that was earmarked for Friday practice sessions rather than in qualifying and the race, it did reduce the team's options to juggle its power-plants over the final races of the season. Having already used up his allowed five race engines this season, Vettel's next change will trigger a 10-place grid penalty.
His teammate Daniel Ricciardo, who is the only realistic challenger to the Mercedes pair for the drivers' championship, was third fastest. The Australian has won two of the past three races and has 166 points compared to 238 for Rosberg and 216 for Hamilton.
''I've got a feeling Mercedes probably have a bit more in the bag,'' Ricciardo said. ''We do too, but probably not enough to get on par with them yet, but hopefully a good night of homework will pay off tomorrow.''
Ferrari's Kimi Raikkonen was fourth fastest. Neither Ferrari driver has qualified better than fourth this season.
While the Italian team's pattern in 2014 has been a decline from Friday practice performance to that in qualifying on Saturday and race on Sunday, the early showing in Singapore indicated they could challenge Red Bull as best of the rest behind Mercedes in Singapore. It was also a boost after a dire performance in their home race at Monza in the previous grand prix, which precipitated the exit of long-time Ferrari company chief Luca di Montezemolo.
While Ferrari was surprisingly strong, Williams would be disappointed with its lap times, with Felipe Massa and Valtteri Bottas down in 17th and 18th, as they struggled on the twisty circuit which negates their straight-line speed.
McLaren's Jenson Button was seventh fastest ahead of the Force India drivers Sergio Perez and Nico Hulkenberg while Toro Rosso's Daniil Kvyat rounded out the top ten.
