Team McLaren-Mercedes have confirmed that Alexander Wurz will not test the new 2005 car, the MP4-20, in January, as he is too tall to fit into it.

Although the team added that the car may be modified to accommodate the Austrian, it is thought this may take some time, and as such Pedro de la Rosa, has effectively been promoted to 'third driver'.

A McLaren spokesperson told "We can confirm that the team has taken the decision to optimise the chassis of next year's car, the MP4-20, around race drivers Kimi Raikkonen, who is 1.75 metres tall, and Juan Pablo Montoya who is 1.68, who are both considerably smaller in height that our third driver, Alex Wurz, who is 1.82.

"As a result Alex currently does not fit comfortably into the MP4-20.

"The team is currently evaluating the modifications necessary to accommodate Alex in the 2005 chassis."

Wurz, who has been with the team since 2000, told that he would still help the team in testing, using the MP4-19B. A similar situation has not occurred in recent years, as David Coulthard, was taller than Raikkonen, and as such the chassis couldn't be as small as the new MP4-20.

"I already know I won't fit into the first few cars that will be made but I can continue testing with the MP4-19B," Wurz stated.

"I hope as soon as the team starts making more chassis for the test team they'll be able to build them with more space in the cockpit so that I can have the possibility to work on the development of the MP4-20.

"But at the moment it's not certain that will be the case."

de la Rosa meanwhile is now favourite to run during Friday free practice at the grand's prix, should McLaren opt to run a third car, something they have stated they will do providing it is to the 'team's advantage'.

Jamie Green, Lewis Hamilton and Alex Lloyd are also all rumoured to be in the frame, after testing the MP4-19 recently at Silverstone, and despite McLaren's statement on Monday, that Mika Hakkinen will concentrate solely on the DTM in 2005, he may also be given the opportunity.

McLaren will be allowed to run a third car during Friday practice in 2005, as they finished fifth in the constructors' championship, and only those teams that finished in the top four are not eligible to do so.

Teams can run any driver, providing he hasn't competed in more than six races in the last two-years.