AUSTIN (Texas) • Lewis Hamilton's hopes of winning his third Formula One world championship at the United States Grand Prix were boosted on Thursday when closest rival Sebastian Vettel announced that he would suffer a 10-place penalty on the starting grid.

Vettel's Ferrari team-mate Kimi Raikkonen will take a similar penalty, which will further reduce the team's chances of beating Hamilton's Mercedes unless the weather, which is expected to be wet, intervenes.

"We will have the hit of a 10-place penalty for a new engine at this event but it has always been the plan, it's not a big secret," Vettel told reporters at the Circuit of the Americas. "Obviously if you look at just this race in isolation, for sure it's not great news but then you have to look at the whole project, the whole season and it was always the plan to have a fresh engine until the end of the season (from) here."

Hamilton, who has won nine of the 15 races so far, leads Vettel by 66 points in the standings with four races left.

His Mercedes team-mate Nico Rosberg is 73 points adrift, which means Hamilton needs to score nine points more than Vettel and two more than Rosberg to be sure of his second successive crown.

A Mercedes one-two, with Hamilton winning, would do that but Rosberg said the Briton would still face a battle with him in tomorrow's race.

"There is nothing to lose. I want to win and I have the opportunity to win," said the German.

"It makes it more simple for us, the weekend," he said of Ferrari's penalties. "But they are still a threat even from where they are because you never know with the weather or whatever."

The new engine will be Vettel's fifth of the season, incurring a penalty because it exceeds the allocation of four, but Ferrari have already hit their targets for the season after failing to win a race last year.

Vettel has won three grands prix this year, the same number as Rosberg, and he and Hamilton are the only drivers to have won in Austin since it first hosted the championship in 2012.

The German, who won his four world championships with Red Bull, has also started twice on pole in Texas.

Hamilton is eager to close the gap. A third drivers' crown for him would place him alongside some of the sport's greats like Jack Brabham, Jackie Stewart, Niki Lauda, Nelson Piquet and childhood hero Ayrton Senna.

"My goal is to win a third title and until I achieve that, there is no other goal," he said. "I love going to Austin - the track has been amazing for me since the first race. I am looking forward to it. It is a track where you can race and get close to people."

REUTERS, AGENCE FRANCE-PRESSE

F1 UNITED STATES GRAND PRIX

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