The McLaren driver Fernando Alonso will miss the Formula One season-opening Australian Grand Prix next week on medical advice.
Doctors have advised the 33-year-old Spaniard, who crashed in testing on February 22nd, not to risk a second concussion by racing in Melbourne.
The two-time champion's place will be taken by 22-year-old Dane Kevin Magnussen, McLaren's reserve driver.
A McLaren statement says Fernando has understood and accepted that advice, and the two McLaren-Honda cars will therefore be driven in Australia by Fernando's teammate Jenson Button and the team's test and reserve driver Kevin Magnussen.
The 33-year-old Spaniard crashed into a wall at the track in Barcelona when he ran wide on the final day of the second pre-season test and had to be air-lifted to hospital under sedation.
Alonso spent three nights in hospital before being released and as a result sat out the final testing session in Barcelona last week so as to rest and recuperate at home in the northern Spanish city of Oviedo.
McLaren remain hopeful that Alonso will be cleared to race in the second Grand Prix of the season in Malaysia on March 29th.
Alonso has only just begun his second spell with the Woking-based team after an ill-fated one-season stint in 2007 when McLaren were expelled from the constructors' championship and fined a record 100 million US dollars for spying on confidential technical information from Ferrari.
On top of Alonso's crash, McLaren have endured significant reliability problems in testing with their new Honda-powered MP4-30 car.