Kimi Antonelli Mercedes ally makes key admission: 'But it was so rough'

Kimi Antonelli's race engineer Peter Bonnington has admitted he did not envisage the Mercedes driver would reach the heights of F1 drivers' champion so early in his career.

Antonelli — who 'Bono', as he is affectionately known, described as a "diamond in the rough" when their partnership began — became Formula 1's youngest champion by finishing third at the Mexico City Grand Prix.