Williams have a hard road ahead.

The former champions have not won a race since October, engine partner BMW [Images] and main sponsor Hewlett-Packard are leaving and Briton Jenson Button [Images] has paid millions to escape his contract.

Some see a Formula One team in decline, low on morale and rocked by one blow after another. In Brazil [Images] on Sunday, Australian Mark Webber [Images] and local man Antonio Pizzonia even collided within seconds of the start.

Co-owner Patrick Head acknowledges the problems but believes the team can come back strongly.

Indeed, Head suspects that BMW motorsport director Mario Theissen may be the one feeling more pressure next year when the German carmaker makes its debut as a full constructor after buying Sauber.

"I think Mario has got a pretty big rod on his back," he told Reuters.

"As I understand it, he's told the BMW board not only that he will arrange that the team is fully funded through sponsorship but also that they will win the championship in 2007. Well, good luck to you Mario.

"In order to get the board to approve the decision to buy Sauber, he made those two promises to them," said the Briton, whose relationship with Theissen has steadily deteriorated over the last year.

"That's what we're told by other board members, anyway; The board members who were present but didn't agree with the joint decision that was made [to buy Sauber]."

BMW have been Williams' partners since 2000 and, while they finished runners-up in 2003, they have won just 10 races together. In 2004 they slipped to fourth overall.

"The first part of this year wasn't brilliant but it was sort of reasonable and the second part of the year has been pretty unimpressive," said Head.

"Our expectation that we would strengthen our position all the way through the season didn't stand up but we are confident we will be strong next year.

"We've sorted out a lot of the problems that we had with our wind tunnels, we are now getting more runs per day of good quality aero work."

GREATER COMFORT

Head recognised that BMW's departure could be seen as a reflection on Williams but felt it was also "to a large extent a reflection on the personal ambitions of Mr Theissen and [BMW board member Burkhard] Goeschel.

"Had, I think, Williams been able to offer the board a greater level of comfort that we were going to be winning championships, then maybe that wouldn't have happened."

The carmaker's departure hastened the exit of Hewlett-Packard and also led to Button reassessing his situation.

The 25-year-old driver, who would have partnered Webber, paid an estimated 18 million pounds ($31.85 million) to extricate himself before signing a long-term deal with Honda-backed BAR.

Williams are also switching to Bridgestone tyres from Michelin, the French company that has dominated the Formula One season with Renault and McLaren.

They will have to pay for a Cosworth V8 engine in 2006, and the team's second driver -- possibly test driver Nico Rosberg -- will not be an expensive signing in order to keep costs down.

Head said that did not mean the team would be merely treading water, however.

"We've obviously seen what BMW were offering us and we've seen what Cosworth are offering us and the latter is quite a lot higher than the spec of the former. A long way," said Head.

COMPETITIVE ENGINE

"Unless somebody is producing an engine that is very special indeed, we have no reason to think that our engine next year will be anything other than competitive," he continued.

"The problem will be whether it will have enough resource around it through the season to develop during the year and the answer at this stage is no.

"But it's one of the things we are working on. There is in the contract an agreed update during the year but there's no way it will have the white heat of development that, say, the Honda engine has on it," he said.

Paddock speculation has suggested that Williams are likely to switch to Toyota in 2007, and an approach was made before the Cosworth deal was announced, but Head said there was no agreement yet in place.

Williams' lack of success has prompted some to call for Head to reassume the technical director role he handed over to Australian Sam Michael last year but he made clear he would not do that.

"My interest at Williams is to assist Sam and to work in the factory to develop our capabilities so that Williams comes back to a competitive position," he said.

"It is not part of my life plan or interest to demonstrate to the outside world that I'm a decent engineer, I have enough self-confidence to know that.

"From my early 20s to early to mid-50s I was used to doing seven days a week and 14-hour days and I don't have an interest in taking that approach."

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