Williams admits to Wurz 'risk'.

Frank Williams has admitted that promoting Williams test driver Alex Wurz into a race seat is a 'risk', but at the same time insisted he was ultimately happy with his decision.

The surprise replacement for Red Bull bound Mark Webber, Wurz has only started a single race since 2000 when he last competed full-time with Benetton, but the Austrian earned himself a spot alongside Nico Rosberg in the team having made his name testing for McLaren-Mercedes and this year for Williams.

Currently in the midst of the worst patch of form in their illustrious history, Frank Williams was eager to temper youth with experience in a bid to avoid in-team rivalry and to also get a broad spectrum of ability. With this in mind, he is more than satisfied with his choice for 2007.

"Formula One is full of risks and we felt he was the best choice available and we are very happy with our decision," he told a Friday press conference ahead of the Turkish Grand Prix.

"We feel that having two young drivers in the team would leave us short of experience and it might increase the probability of them fighting between the pair of them and with the seniors on the track."

Williams also pronounced himself pleased with the decision to switch from Cosworth engines to Toyota units for next season, citing their greater development potential as being a prime reason why they have switched from independent to major manufacturer backing.

"I don't think Cosworth would be unhappy if I pointed out that Toyota have much more development and resource available to them and it does not proceed at a faster pace as the manufacturers engines further up the grid. So we have tagged on with our friends at Tokyo."

Toyota team principal John Howett was equally happy to have concluded a deal with Williams and switching their allegiance from MF1 Racing, despite being aware that they could prove more competitive than their current customer team.

"Toyota's position is to win with our own team and we are happy to have been selected by Williams. They are a great team with great heritage and we will deliver a great engine to them. And if we don't we'll get big pressure from them."