When it was announced that in 2007 teams would no longer be able to use three drivers in Friday practice sessions, it was clear that this would have an impact on up and coming drivers, robbing them not only of an opportunity to gain F1 knowledge, but also the chance to strut their stuff in front of the assembled team bosses.

Then came the change to the testing rules, which stated that teams could only use one car, and that mileage would be restricted.

As predicted, this has come as a serious blow to drivers keen to make the step up to F1, and leaves team bosses with a dilemma. BMW's Mario Theissen, in particular, is not happy. Having run Sebastian Vettel in the Friday sessions in the opening races - much to the frustration of Nick Heidfeld - the German re-evaluated his team's approach ahead of the Spanish race.

"After we had Sebastian in the car in the first races on Friday mornings, we sat down with the engineers and had a look at what we achieved. I have to say that especially in Malaysia where we were not well sorted on Friday, we came to the conclusion that it would have been more beneficial to have the race driver in the car for the entire day.

"It was really a tough decision for me to take," he admitted, "because with this year's test restrictions, you can hardly bring a young driver up to Formula One any more. There is just not enough opportunity. You have the Friday but then only a few days testing and those days only with one car, so there is really no comparison and we normally have a big programme at a test. So I think it would be good for next season to re-think the test restrictions and do something for young drivers."

The German has the support of Red Bull boss, Christian Horner: "I agree fundamentally with Mario's comments," he admitted. "I think that track time is at a premium now for the race drivers in the way that the test agreement with the single car and reduced days has obviously gone. The moving away from running a third car on a Friday and obviously with the Friday running that we currently have - again being limited track time - you want to put your race drivers in to optimise the amount of time they're on circuit and in the car developing it.

"I think we need to think carefully about testing regulations going forward because for sure, it is losing the ability to put youngsters in the car, from a team point of view. It's something that does need careful consideration and again, how we go about things with Friday practice.

"I think it's going to be very tough for youngsters under the current regulations and testing agreement to actually break into running in the car," he added, "because track time is at an absolute premium and I can't see us putting youngsters in the car before the end of the season."