Nico Rosberg began his Belgian Grand Prix weekend in emphatic fashion after soaring to the top of the timesheets as Formula One roared back into action following its mid-season break.
After Lewis Hamilton was penalised with at least a 15-place grid penalty for taking on a fresh engine here, Rosberg, who is 19 points behind his Mercedes team-mate in the championship battle, is expected to cruise to what will be a much-needed victory.
And Rosberg started in style by posting a best lap of one minute and 48.438 seconds to finish the opening practice session at the historic Spa-Francorchamps circuit comfortably faster than Hamilton.
The Englishman, who has turned a 43-point deficit to Rosberg into a 19-point lead by virtue of winning six of the last seven grands prix, faces the improbable task of continuing his victorious run following his penalty.
Hamilton, who was 0.730 seconds slower than Rosberg on Friday morning, will start no higher than 16th after his Mercedes team confirmed he had taken on new parts to his engine, thus exceeding the five he is allowed before a penalty is enforced.
Kimi Raikkonen was third for Ferrari with Force India's Sergio Perez, the only other driver within one second of Rosberg, in fourth.
While the Belgian Grand Prix is often synonymous with inclement weather, the longest circuit on the Formula One calender was bathed in sunshine as unseasonably warm temperatures continued to sweep through the Ardennes.
Sebastian Vettel was fifth for Ferrari, 1.4 seconds adrift of Rosberg, with Red Bull's Daniel Ricciardo sixth. Jenson Button was only 18th for McLaren.
Rosberg and Ricciardo were also among a number of drivers to trial the Halo during opening practice.
Plans for the controversial cockpit protection device to become mandatory in the sport have been shelved until 2018 following a meeting of F1's strategy group last month.
But the Halo will continue to be tested, with the device attached to Rosberg and Ricciardo's cars on Friday. Carlos Sainz and Nico Hulkenberg also ran the Halo.
British rookie Jolyon Palmer is fighting to convince his Renault bosses to extend his contract into a second season, but his running was curtailed by an mechanical issue and he propped up the timesheets with Fernando Alonso, who was unable to post a competitive time following a water leak.
Source: PA
