We need to be concerned about Williams — Michael Schumacher

WORLD CHAMPION Michael Schumacher has warned that Ferrari will face one of their toughest ever battles if they are to hang on to their world championship crown.

After Ralf Schumacher and Juan Pablo Montoya secured a second successive one-two to win the French Grand Prix, the five-time champion said that the setback French GP, and Williams win at the Nurburgring, had shown that Ferrari now face genuine challengers.

"We need to be concerned about Williams," said Schumacher who finished 19.5secs behind his brother while team-mate Rubens Barrichello was back in seventh spot after a spin on the first lap had plunged him into last place.

"We know what they do and we must get our act together," said Schumacher.

"Looking at the weekend here, what we achieved was as well as we could have done. But we have to improve the situation and we have a big test coming up. We will all have to try very hard.

"What we need to do is keep concentrated to get our act together and improve the situation.

"Everyone knows what needs to be done but I can't tell you what it is because Ralf is listening. I won't divulge secrets. All I can say is that we have a very good car, so do Williams."

In the last two races, while Williams have collected 36 points, Ferrari have scored just 18. The German, however, insists, the team won't panic.

"We have had phases in the past when we were behind and we recovered. I am confident we can turn it around and all in all I gained another point in the championship over Kimi."

Schumacher had started from third but lost his place to McLaren's Kimi Raikkonen at the first turn and then slumped to fifth behind David Coulthard before the Scotsman suffered a disastrous pit stop when he pulled away with the fuel hose still attached.

"Kimi simply out-accelerated me and David was very close. It was quite exciting. We ran five laps longer than Kimi at the last stop to get on the podium. That was the only opportunity for me. We hoped our tyres would hold out and that gave us the advantage."

Ralf Schumacher predicted there's more to come from his born-again team.

Neither Williams man looked troubled as the team moved to within just three points of Ferrari in the constructors' championship.

"We had a one-two last week and again today and hopefully the two of us can keep going," said Ralf.

"There will be plenty of circuits which don't suit us but we have a long test ahead of us. We are going in the right direction and hopefully we can continue it.

"As far as a title challenge is concerned, in Formula One you can never be too confident but every driver would love to win a world title. I have waited a long time and it might be possible this year."

The only threat to Ralf was from his team-mate who cut the lead to just under two seconds at one time before winning comfortably. But Montoya said he was happy.

"I wasn't comfortable with the car early in the race and I was calling the pits every half lap to see what I can do about it," said Montoya. It got better and I had the fastest lap. I needed another second but it wasn't there."