Nico Rosberg's bid to win a hat-trick of consecutive races in Austria hangs in the balance after he dramatically crashed out of final practice.
After suffering a rear-left suspension failure, Rosberg, who heads Lewis Hamilton by 24 points in the championship, lost control of his Mercedes on the exit of turn three and smashed into the barriers.
He sustained significant damage to his chassis in the crash, and will serve a five-place grid penalty after Mercedes were forced to fit a new gearbox.
The incident, which took place with 20 minutes of the one-hour session remaining, immediately saw the red flags issued as Rosberg's Mercedes came to a halt on the centre of the track.
A furious Rosberg hitched a lift back to the paddock before his car was put on to the back of a pick-up truck and taken to the Mercedes garage.
It is from there where his crew will try to determine the cause of the apparent suspension failure.
Rosberg's troubles capped a difficult session for Mercedes, Formula One's all-conquering team, with Hamilton, who ran off the track at turn eight, struggling with blistered rear tyres.
"Take a look at my rears," a concerned Hamilton said over the team radio. "Something is not right. I am going to go off if I keep going."
The Briton, who is yet to win in Spielberg, returned to the Mercedes garage, and when he headed back on to the track with 10 minutes left, his best time was good enough for only third with Sebastian Vettel setting a new lap record to lead a Ferrari one-two ahead of team-mate Kimi Raikkonen.
Vettel, however, is set to carry a five-place grid penalty into qualifying after an unscheduled gearbox change.
Elsewhere, the Red Bull duo of Daniel Ricciardo and Max Verstappen were fourth and fifth in the order with McLaren's Jenson Button ninth fastest.
British rookie Jolyon Palmer was 17th, nearly half-a-second slower than his Renault team-mate Kevin Magnussen.