SUZUKA, Japan (Reuters) - Formula One world champions Mercedes see resurgent Ferrari as a genuine threat and have done since early in the season, Lewis Hamilton and Nico Rosberg said at the Japanese Grand Prix on Thursday.
Speaking to reporters only days after Sebastian Vettel won in Singapore for his third victory in 13 races for the Italian team, the Mercedes team mates agreed Ferrari were firmly on their radar.
"They are a threat and we do take them very seriously," said Rosberg, who is second in the championship -- 41 points behind Hamilton but now only eight clear of Vettel with six races remaining.
"They have been a threat at various times throughout the whole season."
Hamilton, who failed to finish in Singapore in his first retirement of the year, said he had never ruled Ferrari out of the equation.
"How seriously I take it (the Ferrari threat) hasn't changed since Malaysia," said the Briton, winner of seven races this year with 11 poles in 12 races until Singapore when Vettel was fastest on Saturday and Sunday.
"For me everyone's a threat and they (Ferrari) have been since Malaysia (in March). Since then they've always been in view... we've been aware of them all year."
Hamilton said post-Singapore analysis of what went wrong in Singapore, where Vettel was a second and a half faster than Mercedes, had produced a lot of explanations for what had happened.
The Singapore street circuit is slow and twisty, unlike Suzuka which has some fearsome high-speed corners, and the race run at night in high humidity.
"I can't tell you what the team have come up with but they have come up with a lot of solutions, a lot of reasons for it being the way it was," said Hamilton.
"The majority of them believe that at least one of the many reasons they came up with had a domino effect. So I'm confident that it's been understood but they will still continue to do analysis for sure."
Vettel, who has now won as many races in his debut season with Ferrari as Michael Schumacher did in his first year at Maranello in 1996, told a separate news conference that he expected Mercedes to be faster in Suzuka.
"In a way it was a big surprise to see Mercedes struggling, which I don't expect to be the case here. Again, it would be a big surprise," said the German.
Editing by Sudipto Ganguly