World champion Jenson Button believes that the returning Michael Schumacher will be as strong as ever and challenge for the title.

In an interview with Welt am Sonntag newspaper, the McLaren driver said that the German seven-time world champion will be as strong as he used to be. “With that, everything is said.” He expects Mercedes, which has taken over from his former team Brawn GP, to be very strong and believes they stand a chance to win the constructors’ title.

Ahead of next week’s opening Grand Prix race in Bahrain, Button sees four teams challenging for victory in the race. “Ferrari, Red Bull, McLaren and Mercedes. Even if some people expect Michael Schumacher not to be so fast, I think he will be.” Button said he thought that Mercedes would be stronger than expected as the team had announced that they were getting new parts for their MGP W01 car.

“However, it is impossible to predict how the season will go.” Last year the English driver seemed to be running away with the championship after winning six of the opening seven races, but then suddenly found himself being challenged by Brawn teammate Rubens Barrichello, as well as the Red Bull duo of Sebastian Vettel and Mark Webber.

Button believes that the new rule changes — especially the refuelling-ban — will introduce some suspense.

The 30-year-old said he is highly motivated in his English team and driving alongside his predecessor as world champion, Lewis Hamilton.

“I do not think I would have been as motivated with Mercedes,” he said.

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