Alonso, who remains in hospital under observation, left the track at Turn 3 of the Catalan circuit, with McLaren’s telemetry data and analysis revealing that his car struck the inside concrete wall, first with its front-right wheel and then with its rear-right.
"(Alonso's) car ran wide at the entry to Turn 3 - which is a fast uphill right-hander - allowing it to run onto the Astroturf that lines the outside of the track," read McLaren’s statement.
"A consequent loss of traction caused a degree of instability, spitting it back towards the inside of the circuit, where it regained traction and struck the wall side-on.
“It was a significant lateral impact, resulting in damage to the front upright and axle. After the initial impact, the car slid down the wall for about 15 seconds before coming to a halt. All four wheels remained attached to the car, but no damage was sustained by the bodywork or crash structure between the front and rear wheels.”
Having outlined their analysis of the accident, McLaren were keen to dismiss what they termed ‘erroneous rumours’ about what had caused the Spaniard to crash: “We can categorically state that there is no evidence that indicates that Fernando’s car suffered mechanical failure of any kind.
“We can also confirm that absolutely no loss of aerodynamic pressure was recorded, which fact indicates that the car did not suffer any aerodynamic loss, despite the fact that it was subjected to a significant level of g-force. Finally, we can also disclose that no electrical discharge or irregularity of any kind occurred in the car’s ERS system, either before, during or after the incident.
“That last point refutes the erroneous rumours that have spread recently to the effect that Fernando was rendered unconscious by an electrical fault. That is simply not true. Our data clearly shows that he was downshifting while applying full brake pressure right up to the moment of the first impact - something that clearly would not have been possible had he been unconscious at the time.”
Having been extracted from his car, Alonso was sedated before being airlifted to hospital where a thorough analysis of his condition, involving CT scans and MRI scans, revealed he had suffered a concussion but no further injuries.
According to McLaren, the double world champion will remain under medical observation “to facilitate a peaceful recuperation” and “to recover from the effects of the medication that successfully managed his routine sedation”.
“We intend to give him every opportunity to make a rapid and complete recovery,” the statement continued, “and will evaluate in due course whether or not he will participate in the next Barcelona test.”
The final pre-season test takes place in Barcelona from February 26 to March 1.