Baku, July 3, AZERTAC
Mercedes are potentially facing a challenge to their supremacy at the Austrian GP after Ferrari set the pace and Nico Rosberg was pitched into a crash by a suspension failure in Practice Three, according to skysports.
After dominating Friday, Mercedes experienced a fraught final build-up to Saturday's later qualifying session as Sebastian Vettel and Kimi Raikkonen unexpectedly set the pace for Ferrari.
Most pressing among them is the cause of Rosberg's heavy shunt and whether they will be able to repair the world championship leader's car in time to take part in qualifying, which begins at 1pm BST.
Mercedes have already confirmed the German will take a five-place grid penalty for a gearbox change.
Exiting Turn Two at the start of a fast lap, something appeared to break on Rosberg's left-rear suspension as he went over the kerb, with the W07 snapping straight left into the barriers.
Rosberg was unharmed and on his return to the garage was seen shaking his head in apparent anger at the accident, which did substantial damage to his car.
The German had been Mercedes' lead runner on Friday and Lewis Hamilton was unable to outpace the Ferraris when the session restarted after the red flag, finishing 0.210s back on the them in third place.