World champion Sebastian Vettel has warned against complacency after a blistering start to the Formula One season with two wins and a second place.

The Red Bull driver will go into Sunday’s Turkish Grand Prix again the favourite, but the 23-year-old told German Press Agency dpa that the season had only started and a lot could happen.

“I think we’ve had a good start to the season but we can’t afford to sit back now as a result of that, but have to continue putting pressure on the competition and giving our best in every race,” Vettel said.

Vettel has a 21-point lead in the drivers’ championship over McLaren’s Lewis Hamilton, but after two commanding wins in Australia and Malaysia, the German had to settle for second place in Shanghai on April 17 behind 2008 world champion Hamilton.

Hamilton’s team-mate Jenson Button is third in the standings, suggesting McLaren are set to be the closest rival for Red Bull this season.

But Vettel said he believed other teams will become more competitive during the course of the year.

“There is still a long way to go in the season and a lot can happen,” he said.

“Fernando Alonso is a good example. A lot of people had written him off last year but he came back and nearly won the world championship.

“That’s why I think we should not lose sight of Ferrari, and Mercedes and Renault should also not be under-estimated.” Vettel said he was “a bit disappointed” after failing to win in Shanghai but two victories and a second place was a good basis for the rest of the season.

“The important thing is to be consistent throughout the season,” he said.

Vettel indicated there would be further improvements for the car for the race in Istanbul, a circuit which saw him crash out last year in a collision with team-mate Mark Webber, with both drivers blaming each other.

Vettel said he had soon put the incident behind him because he always looked ahead to the next race.

“I can’t change things that have happened. More importantly I could learn from them,” he said.

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