SPIELBERG, Austria (AP) Sebastian Vettel gave Mercedes something to think about after posting the fastest time in the second practice session of the Austrian Grand Prix on Friday, despite spending a large part of the day stuck in the Ferrari garage.
Vettel recovered from a brake problem in the morning session, when he managed only four laps, to go quickest in the afternoon - but then had that session cut short because of a sensor problem on his gearbox.
''Always better it happens in practice than the race, but we need to understand what happened and make sure it doesn't happen again,'' said Vettel, a four-time Formula One champion. ''We know that we have a good car, and that it works well around here. I didn't get many laps today, but the car felt good and competitive.''
Vettel beat Mercedes' Rosberg by 0.011 seconds in the second practice, with championship leader Lewis Hamilton trailing back in fifth.
The time gaps are small on this circuit, which has the shortest lap time of the season, giving Ferrari less of a disadvantage compared to Mercedes in terms of race speed.
''Hopefully we can stay with Mercedes as much as possible and then it will be an interesting qualifying,'' said Vettel, the only driver other than Mercedes pair Hamilton and Rosberg to win a race this season.
In a further boost for Ferrari, his teammate Kimi Raikkonen, was third quickest, 0.260 behind, to match his position from the morning, when Rosberg was quickest ahead of Hamilton.
''The red cars (Ferraris) are very strong here. They had very impressive pace on higher fuel levels as well as low,'' Rosberg said. ''We will definitely need to work hard to find a few tenths for tomorrow.''
It was a frustrating P2 for Hamilton, as he managed only the fifth best time behind Lotus driver Pastor Maldonado in cool, windy conditions.
''I had a bit of oversteer here and there,'' said Hamilton, who ran wide on a couple of turns. ''There's just not a lot of grip out there on track and I didn't put a full lap together. I had some good sectors and was a few tenths up on a couple of laps, so the pace is there.''
Hamilton has four wins to Rosberg's two so far this season, but remains wary of Ferrari on the tightly-strung Red Bull Ring track.
''Ferrari looked quick and it's definitely closer here than at other circuits,'' said Hamilton, who won the Canadian GP two weeks ago to move 17 points ahead of Rosberg overall. ''Hopefully it'll all come together tomorrow.''
Felipe Massa secured pole position for Williams last year - the only driver to beat Mercedes to pole all season - but practice did not go well, and he finished 15th in P2.
''I have no balance at all,'' he lamented.
Still, at least the Brazilian showed his reflexes are in fine shape. Thirty minutes into the morning session, he slammed the brakes as Ferrari team principal Maurizio Arrivabene accidentally walked out in front of him in the pit lane.
There was no harm done, as a smiling Arrivabene quickly scampered out of the way, and Massa - a former Ferrari driver - waved to him.
There were no smiles for McLaren after another tough day.
Fernando Alonso was 16th and Jenson Button 18th in the afternoon run.
Alonso will start the race from the back of the grid because he has used his four allocated engines.