Rosberg heads Hamilton in practice

Nico Rosberg set the pace in opening practice for the German Grand Prix on Friday morning ahead of fellow Mercedes driver Lewis Hamilton.

The World Championship leader lapped the 4.574km Hockenheim circuit in a time of 1:19.131s to go 0.065s quicker than Hamilton, whose British GP win two weeks ago pulled him to within four points of his team-mate and title rival in the standings.

Rosberg was made to endure his first retirement of the season at Silverstone but has had plenty to celebrate since, not least his marriage but also, of course, Germany's World Cup win - although his plan to further mark the latter success on home soil this weekend fell foul of FIFA on Thursday.

The session was also the first in which cars took to the track after F1's own governing body confirmed that FRIC suspension - the legality of which the FIA questioned last week - had been removed by all teams.

Mercedes were said to have the best-developed FRIC system and the fact that the Silver Arrows once again ran one-two goes some way towards confirming the belief held by many that, in this instance, changing the rules hardly constitutes a game-changer.

Even so, plenty cars were ran wide during the session and besides the question of how drivers might adapt - if indeed they need to - the change is sure to provoke more debate heading into the weekend: how the combination of FRIC-less cars, the two softest compound tyres and baking hot temperatures that look set to continue into the weekend might affect tyre wear being an obvious example.

Fernando Alonso was third fastest in his Ferrari, about 0.3s off Rosberg's pace, with Daniel Ricciardo's Red Bull fourth ahead of Jenson Button's McLaren and Sebastian Vettel's Red Bull.

Behind the defending champion, Kevin Magnussen (McLaren), Kimi Raikkonen (Ferrari), Daniil Kvyat (Toro Rosso) and Adrian Sutil (Sauber) completed the top ten.

Felipe Massa's Williams was next up with the Brazilian ending the session four places, and about 0.2s faster than Susie Wolff's sister car.

It's an outcome that must have come as a relief to the Scot, who had briefly looked set for a repeat of her Silverstone disappointment as she limped round her installation lap.

However, a software glitch was soon diagnosed and fixed, allowing Wolff to complete a total of 22 laps.