Fernando Alonso had barely completed a handful of laps before causing a red flag during the opening day of pre-season testing at the Circuit de Barcelona-Catalunya.
The Spaniard ended up in the gravel at the final corner with just three wheels on his McLaren MCL33, the fourth wheel some 50 metres away.
That caused the first red flag of testing after less than 40 minutes of running; marshals quickly rushed to the aid of the McLaren, which was swiftly recovered, allowing the session to resume after a brief break.
McLaren confirmed that a wheel nut issue was to blame, with its running expected to resume after the lunch break.
The issue isn't the best start for McLaren which endured three years of pain with former engine supplier Honda and had hoped for a trouble-free day with new partner Renault.
