Singapore - Formula 1 leader Lewis Hamilton goes into Sunday's inaugural Singapore Grand Prix in fighting mood after losing his appeal against the penalty imposed on him in Belgium.

"People will probably expect me to be depressed about the result, but that isn't me," the McLaren-Mercedes driver said.

The 23-year-old Briton is one point ahead of Ferrari rival Felipe Massas as Formula One gets to grips with its first-ever night race, the first of the season's four remaining races.

"All I want to do now is put this matter behind me and get on with what we drivers do best: racing each other," Hamilton said.

"We're racers, we're naturally competitive, and we love to overtake.

"Overtaking is difficult, and it feels great when you manage to pull off a great passing manoeuvre. So I'm disappointed, yes, but not, but not depressed."

The world motorsport body FIA on Tuesday dismissed the appeal from McLaren-Mercedes against the 25-second penalty that Hamilton received for cutting a chicane in the Belgium Grand Prix.

Martin Whitmarsh, McLaren's chief operating officer, said: "No-one wants to win Grands Prix in court, but we felt that Lewis had won the Belgian Grand Prix, on track, in an exciting and impressive manner.

"Our legal team and witnesses calmly explained this, as well as our belief that the appeal should be admissible, to the FIA International Court of Appeal.

"It nonetheless decided that our appeal was inadmissible. We will now concentrate on the remaining four races of the 2008 Formula 1 season."

Hamilton has the temperament to put the setback behind him for Sunday's floodlit race on a 5,067-metre street circuit which winds through the heart of the city-state.

The lighting system consists of 108,423 metres of power cables, 240 steel pylons and 1,500 light projectors, creating light that is four times brighter than that used at sports stadiums.

The drivers will also have to get used to a later, evening start - allowing European television viewers to watch the race in the usual afternoon slot - and the prospect of rain mixing with the glare of the lights to add another unknown quantity.

Mercedes sports chief Norbert Haug said: "In normal conditions the lighting will make conditions better than what we sometimes experience with light and shade. However if it should rain the lighting won't be helpful."

Hamilton for one won't be changing his racing style.

"I'm in the lead because I've made fewer mistakes. You have to enter each race with heart but you also have to be smart," he told BBC Sport.

Hamilton finished seventh in the Italian Grand Prix won by Germany's Sebastian Vettel in a Toro Rosso , but Monza, where the Briton's chances were ruined by a poor qualifying result, is now long forgotten.

"I really have a skill where I am able to put a previous disappointment behind me," he said.

Hamilton, on 78 points, and Massa, on 77, are now the big favourites for the title, but Haug says it is too soon to write off other challengers including BMW Sauber driver Robert Kubica (64) and Ferrari's defending champion Kimi Raikkonen of Finland (57).