Ferrari power gap now 'zero' - Lauda

Ferrari transformed its fortunes during the winter, bouncing back from a 2014 season to forget to emerge as Mercedes' closest challenger, with Sebastian Vettel taking victory in the Malaysian Grand Prix.

While Mercedes has won the other three races so far this year with reigning world champion Lewis Hamilton, Ferrari has remained a threat, and Lauda believes that is down to the progress it has made with its power unit.

"Ferrari has closed the gap from last year to this year to nearly zero," Lauda said in an interview with the Red Bull Content Pool newsroom.

"I think they increased their engine by about 45 horsepower, so my estimate at the moment is that they have the same power Mercedes has.

"So now the difference depends on the car, and what the drivers do.

"The season is not finished - we've only had four races and there will be close racing all the way through the season.

"Ferrari is very strong, there is no question about it, and as a racing team you should never think that nobody can catch you - that is a big mistake."

Ferrari's upturn in form has moved it clear of the rest of the pack chasing Mercedes, leaving 2014 frontrunners Williams and Red Bull playing catch-up.

Red Bull driver Daniel Ricciardo added: "Ferrari have been the biggest movers. Winning the second race was a big step.

"Last season we were clearly in front of them, but they've made a big step in the off-season.

"They've done a lot of work, and clearly they've closed the gap by about a second.

"Now they're within half a second, if not less, so they've made a big gain.

"At the moment we are not on the pace of Mercedes and Ferrari, but for us it's good to see that a step like that is possible."

Lauda described Williams's start of the season as "a little bit disappointing", and while he believes that the British squad will catch up, Red Bull motorsport advisor Helmut Marko feels that his team has Williams in its sights.

"Williams is the third fastest team at the moment, but we showed in Bahrain that we are closing and closing," said Marko.

"We will work as hard as possible at least to produce the best chassis, so even if the engine is not as strong as the Mercedes one, we can challenge them in the near future."