Jun.20 (GMM) The proposed change to the safety car rules drew a mixed reaction from the drivers as it was tested at the Magny-Cours circuit on Friday.

After the chequered flag of the afternoon practice session for the French grand prix, race control simulated a safety car period, with marshals holding out 'SC' boards.

Utilising special software for the standard ECU, each driver was sent a message by race control and had five seconds to respond by pressing a button.

A target minimum lap-time was then calculated and displayed on the driver's dash, which they then had to monitor as they slowly made their way back to the pits.

The proposed system is an alternative to the current situation, where drivers can be unfairly penalised due to the pitlane closing upon immediate deployment of the safety car.

Some drivers, however - such as McLaren's Lewis Hamilton - said after the trial that constantly monitoring the 'delta' lap-time was distracting.

"It still needs a little more work at the moment," he added.

Williams' Nico Rosberg agreed: "It's a bit strange because you have to look at your dash quite a lot and at the same time you're probably going to be passing the incident and everything.

"But we really need to find something to improve the current thing -- it could be a step forward, we will see."

Toro Rosso's Sebastien Bourdais, meanwhile, explained that despite his delta lap-time, the car in front of him was travelling too slowly.

"We will see how it plays out," the Frenchman said.

Reigning world champion Kimi Raikkonen seemed happier with the system following the Friday trial.

"I think it could be a good solution because it puts everyone in the same situation and that way, you can't be penalised just by unfortunate circumstances," he said.