Melbourne: Fernando Alonso's mysterious crash has put McLaren on the back foot before the Formula One season has even started in what threatens to be another tough year for the team.

Speculation over the accident during testing is increasing rather than abating as Alonso prepares to sit out this week's season-opener in Australia on medical advice. A report that Alonso, 33, thought it was 1995 and he was still in go-karting when he regained consciousness was dismissed as "nonsense" by his manager Flavio Briatore.