Austrian Grand Prix 2015: Nico Rosberg sets the benchmark in first practice as Sebastian Vettel completes just four laps

Lewis Hamilton finished three-tenths slower than his Mercedes team-mate as the rest of the field showed little sign of challenging the front-runners

Nico Rosberg finished fastest in first practice for the Austrian Grand Prix (AP)

Nico Rosberg set the pace in the first practice session ahead of Sunday's Austrian Grand Prix.

The Mercedes man saw off team-mate and championship leader Lewis Hamilton by three-tenths of a second to claim top spot on the timesheet.

Rosberg, who won here last year, clocked a time of one minute 10.401 in a dry session, with rain expected to affect running in Friday's afternoon practice.

Reigning champion Hamilton was second fastest as the Mercedes once again showed their dominance over the rest of the field.

Sebastian Vettel has been the man to push the Mercedes for much of the season but he only managed four laps before losing drive in his Ferrari - with the issue enough to keep him in the pits for the remainder of the session and put him at the bottom of the pile.

Hamilton during practice for the Austrian GP (AP)

The sister Ferrari of Kimi Raikkonen clocked up only nine laps but that was still enough to take third place, with the Finn the only man other than Hamilton to get within a second of Rosberg's best effort.

Williams locked out the front row in qualifying here 12 months ago but Valtteri Bottas could only take fourth, with team-mate and last year's pole sitter Felipe Massa down in ninth.

Massa's fellow Brazilian Felipe Nasr impressed to take fifth for Sauber, whilst the Red Bull duo of Daniil Kvyat and Daniel Ricciardo were sixth and seventh at the team's home grand prix.

Max Verstappen was eighth for Toro Rosso, with the Force India of Sergio Perez rounding out the top 10.

The second Toro Rosso of Carlos Sainz was 11th with Pastor Maldonado's Lotus 12th and Perez's team-mate and Le Mans winner Nico Hulkenberg a place further back.

Jolyon Palmer, stepping in for Romain Grosjean for FP1, was 14th ahead of the Sauber of Marcus Ericsson.

Fernando Alonso will take a hefty grid penalty after qualifying as he changes several parts of his power unit and the Spaniard's reliability woes hit again.

His McLaren was set to carry a number of upgrades that were not available to team-mate Jenson Button but a problem in the very early stages saw him remain in the garage for over an hour - losing valuable assessment time and he was 17th at the chequered flag.

Button had no such issues but could only go 16th fastest after complaining of cold tyres - whilst the Manors of Will Stevens and Roberto Mehri were 17th and 18th, respectively.

PA