SEPANG, Malaysia (Reuters) - McLaren's Lewis Hamilton needed less than an hour of the first free practice session for the Malaysian Grand Prix on Friday to show that he will be the man to beat in this weekend's race.
The 2008 world champion scorched to the fastest time of the 90-minute session on a glorious sunny morning south of the Malaysian capital, clocking one minute, 38.021 seconds to beat the rest of the field by more than half a second.
As the afternoon forecast for heavy rain failed to materialise, the Briton topped the timesheets again in a marginally slower time with McLaren and Mercedes primed to battle it out for pole as Red Bull and Ferrari struggled for pace.
"The car's been quite good. Made some set-up changes which I'm much happier with and now just focusing on the long run pace," Hamilton told reporters. "I didn't get too many laps but its definitely working - it feels good at the moment."
World champion Sebastian Vettel was second fastest in the morning with a time of 1:38.535, just ahead of the Mercedes pair Nico Rosberg and Michael Schumacher, who were separated by just 13 hundredths of a second.
However, Vettel complained over the team radio that his Red Bull "was all over the place" as he toiled in the afternoon heat and could only set the 10th fastest time, more than a second behind Hamilton.
The drivers used both sessions to gauge tyre degradation around the demanding Sepang circuit and with times slowing by around a second after 10 laps, pit stop strategy for Sunday's race will be a key factor in determining the eventual winner.
"Well this track obviously you've got two very long straights so overtaking is probably a little bit more possible than in the last race but still, starting from the front is a much better position to be in and so that's what I'm going for," Hamilton added.
McLaren locked up the front row in the season-opening race in Melbourne last week, with Hamilton's team mate Jenson Button going on to win comfortably, but the Briton had a far bumpier ride in the morning before picking up his pace later on.
The 2009 world champion, who won at the circuit in the same year, struggled with an oil leak that limited his session to just 15 laps in which he could only post the ninth-fasted time, 1.302 seconds behind his team mate.
With his McLaren patched up for the second 90-minute spell, Button was third quickest, splitting Schumacher and Rosberg, who were once again very well matched around the 5.543km circuit.
Romain Grosjean proved his third place on the grid in Australia was no fluke with another strong showing in his Lotus, the Frenchman overcoming early problems with his rear wing to clock the fifth-fastest time in the morning.
Toro Rosso's Daniel Ricciardo matched Grosjean's feat in the latter session and will be delighted to have edged out Ferrari's Fernando Alonso, who showed a marked improvement from his early times but was still 0.719 seconds behind the leader.
Vettel's Red Bull team mate Mark Webber also looked far from comfortable, finishing sixth and seventh respectively, while Felipe Massa fared even worse in the Ferrari despite being fitted with a new chassis for this week's race.
The team reported Alonso's car to be "better in the long run" after improving from 15th to sixth but his Brazilian team mate was 13th in the early session and dropped three places back in the latter run.
"We need to concentrate on scoring points, as many points as possible," Massa said.
"How many? We'll see how the car goes tomorrow in qualifying and in the race as well. We don't have a very competitive car but I hope we can be able to fight to score some points."
HRT had looked in danger of missing out on Sunday's race as they did last week with Narain Karthikeyan, who only managed seven laps before stopping with a hydraulics failure, and Pedro de la Rosa lapping more than seven seconds off the pace.
Both cars set times marginally outside than the 107 percent time limit behind the leader that if they were duplicated in qualifying on Saturday, would omit them from the starting grid.
The pair improved enough to suggest qualification was possible but the Indian driver ended the day in ignominious fashion, spinning off the track on the last bend in the final seconds of Friday's action.