Lewis Hamilton has issued an ominous warning to his rivals.

The reigning world champion has won three of the four races so far this season, leaving his Mercedes teammate Nico Rosberg trailing in his wake.

Niki Lauda says the German, Rosberg, needs to hit a metaphorical 'reset' now and start his 2015 campaign afresh, but veteran Jenson Button says that is not easy to do.

"When your teammate beats you for two or three races on the trot it hurts," he said.

"You have to take it on the chin, look at the reasons why and move forward but it's easier said than done. You have moments where you doubt yourself," added Button.

"Sometimes you're on a high and sometimes you're on a low. It makes a massive difference," he said.

So in stark contrast to Rosberg's low, then, is Hamilton's high.

"I want the third title," he told Wednesday's Sport Bild, "like Senna."

The Briton is already 27 points clear, visibly happier and more relaxed than ever, and - in Lauda's words - in "top form".

"It feels like Sebastian (Vettel) in the year after his first title," Hamilton is quoted as saying.

Famously, Vettel fought tooth-and-nail against Red Bull teammate Mark Webber in 2010, before utterly crushing the Australian and every other rival in 2011.

The German went on to also win in 2012 and 2013, and was often accused of cruising to his poles and victories all too easily.

"It's like you're hovering on a cloud of success," Hamilton explained this week. "I'm still hungry for victory, but at the same time I'm much more relaxed."

The 30-year-old said managing to find a new gear for 2015 has even been a surprise.

"I was thinking more likely it's going to go the other way," said Hamilton, "but I have almost surprised myself - how I have been driving, how I have been adapting to things.

"I have been really proud of it generally."
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