Mercedes 'love' title fight with Ferrari & Red Bull - Toto Wolff

World champion Lewis Hamilton has finished second, third and fourth in the first three races this season

Mercedes say they are "excited" by the "massive challenge" of their title fight with Ferrari and Red Bull.

Mercedes have failed to win any of the first three races and defending champion Lewis Hamilton trails Ferrari's Sebastian Vettel, the championship leader, by nine points.

"Last year we were in a tough fight with Ferrari," said Mercedes F1 boss Toto Wolff.

"However, it was nothing compared to the intensity of this year's battle."

He added: "Not everyone likes this kind of challenge but we love it."

Last year, Vettel led the championship for the first 12 races before Hamilton overhauled him with a run of five wins in six races that, together with a combination of team and driver errors by Ferrari, secured the Briton a fourth drivers' title.

This year, Vettel has won the first two races in Australia and Bahrain, while Red Bull's Daniel Ricciardo triumphed in the most recent race in China.

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Wolff said Mercedes, who have won the past four championships, head to this weekend's Azerbaijan Grand Prix in Baku "excited by the unpredictability" of "an amazing battle in which every detail counts and with an outcome no-one can predict".

He added: "The 2018 F1 season is set to be a celebration of everything we love about motor racing.

"Three teams are fighting fiercely for race wins. We've witnessed exciting races with nail-biting overtakes - the fastest F1 cars in history, driven by some of the best drivers this sport has seen.

"So far, this year has all the ingredients for one of those legendary F1 seasons - a season that fans will look back on with smiles on their faces in years to come.

"It's not just the fans at home or at the race track who are excited - we feel the same. And we know that we have a massive challenge on our hands.

"Both Red Bull and Ferrari will do everything they can to beat us. Their cars, their teams, their drivers - all of them operate at a high level and will continue to put us under pressure.

"Each member of our team joined this sport for these moments."

Hamilton finished fourth in China and has been beaten in qualifying and in the race by team-mate Valtteri Bottas in two of the season's three races.

He said after the Chinese Grand Prix that he needed to go away and "figure out" why he "didn't have the pace".

F1 returns to Baku this year in a new date in April, the previous two events having been held in June.

Last year's race was one of the most dramatic of the season. Vettel deliberately drove into Hamilton in a road-rage incident and Ricciardo won after dropping to 18th after a series of crashes, incidents and safety-car periods.