Mercedes wary of rivals after rule changes, says Wolff
Lewis Hamilton's Mercedes team are preparing for Sunday's season-opening Australian Grand Prix uncertain if they are still the all-conquering force of Formula One.
Mercedes have won 51 of the last 59 grands prix en route to claiming three consecutive drivers' and constructors' championships during an unprecedented reign of dominance.
But changes to the sport's technical rulebook during the off-season has offered fresh hope to Mercedes' rivals, and it is not clear whether the Brackley-based team will still be the ones to beat in Albert Park this weekend.
Indeed, Ferrari, whose challenge will be spearheaded by four-time World champion Sebastian Vettel, enjoyed eight strong days of testing in Barcelona. And the Italian team, who failed to register a single victory last year and are without a drivers' champion in more than a decade, will head into the new campaign cautiously optimistic.
"What we've seen from Barcelona is that the margins at the front of the field have shrunk," Mercedes boss Toto Wolff said.
"We'll see how that pans out in Melbourne, because we still don't know about the fuel loads, weights or power settings of the other cars. But we have done the best job we possibly could over the winter and, if we are not the fastest in Melbourne, then it's about finding out why."
Hamilton will be partnered by Finnish driver Valtteri Bottas this year following Nico Rosberg's retirement.
Hamilton, 32, is aiming to become the first British driver to win four championships.