Theissen doubts Mika return

Hakkinen has held talks with Williams team boss Frank Williams about a seat in 2005 alongside Australia's Mark Webber, but Theissen remains unconvinced that hakkinen could return to the cockpit and be as committed as he was before he retired.

"I think it would be difficult, especially if you have achieved so much," Theissen told Autosport. "He certainly has all the ability and the driving talent that you need. The question is would he still take the risks and be as motivated as he was when he went for his first championship?"

Hakkinen has been in training and is now super-fit after shedding weight over the past few months. However, at 35 years-old, he would be one of the oldest drivers on the grid.

Theissen dispelled the notion that the team would prefer a German driver, such as Jordan's Nick Heidfeld, who the team tried to get in the seat for the German Grand Prix last month. Instead he said the only criteria the squad has for its new employee is speed.

"Nick is in the frame, like several others, but not because he is German," Theissen said. "We really don't look at this. It's only in Germany that we would benefit from his nationality. Basically there's just one major criteria - he has to be fast. It's not about marketing. Of course you would like to have a guy that's good at everything, but the first thing is to be successful. If the driver is not quick, forget about it.

"If you look at a quick fix in a difficult situation, you might go for an experienced driver who's just available," he added. "If you look for the future, you would try to build up a young guy who joins F1. If you want to be strong next season, you need a guy who's really right at that point."

Theissen insisted that the team would name its second driver by the end of the season to ensure he could test from the off in November.

"The target will be to have the second driver confirmed by the end of the season in order to have him in the car in the November tests."