UNDER PRESSURE: Mercedes' Nico Rosberg will start the 2015 Singapore GP in sixth place. Image: AP / Joseph Nair
Singaproe - As Mercedes' long and dominant form mysteriously disappeared under the Singapore floodlights, it did not take long for speculation to begin.
Everyone at Marina Bay and beyond could not believe that, just two weeks after the utter domination of Monza, the silver cars are suddenly much slower than Ferrari and Red Bull.
'We did see this coming'
Nico Rosberg said after qualifying: "When I saw Sebastian (Vettel's) time I thought 'What the hell?'. We did not see this coming."
He admitted that, in the past couple of years of Mercedes' utter domination of the 'power unit' era, the Singapore situation is unprecedented.
As it happened: 2015 Singapore GP - Qualifying
Rosberg said: "We had a dominant car and now we are one and a half seconds behind. Unbelievable. I just looked at Vettel's onboard lap, and it's like he's in a different category."
Hamilton's record bid crushed
Lewis Hamilton, whose shot at equalling hero Ayrton Senna's victory tally on Sunday now appears unlikely, called for Mercedes to look urgently into the matter.
Hamilton said: "I don't know really what we've got wrong."
The early paddock theory is that, having dominated at Monza but only narrowly avoiding disqualification over the tyre pressure saga, Mercedes is now struggling for pace as Pirelli strictly enforces the new guidelines.
Hamilton said: "These tyres for some reason aren't working on our car. I'm challenging my team to find out what it is, whether it's tyre pressures or temperatures or blankets or ride heights, I'm asking."
Team boss Toto Wolff, however, scoffed at rumours Mercedes was only dominating before because it was regularly skating beneath Pirelli's tyre pressure guidelines.
Wolff said: "It's no conspiracy. It's paranoia. We didn't do anything dodgy. It was cleared by the FIA. The Pirelli limits were no contributing factor to our performance."
He acknowledged, however, that Mercedes now has crucial work to do to understand the true cause.
Wolff said: "It is not just for the race here, which will be very difficult anyway even though we will give everything, but it is very important that we do not make the same mistakes that we made here in the next weekends."
Watch: Lewis Hamilton reveals his 'coolest car'
2015 Singapore Grand Prix at Marina Bay Street Circuit: Results
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