The World Supersport race at the Moscow Raceway has been postponed after a huge accident on the back straight in treacherous conditions forced a red flag.

Getting underway in steady rain, the 30-strong field managed to negotiate the opening bends but a fall for Go Eleven Kawasaki's Andrea Antonelli down the back straight created confusion in the blinding spray, the Italian seemingly struck at speed by Lorenzo Zanetti.

Prompting the red flags, though Zanetti was seen to be walking away from the incident, Antonelli was being treated by medical staff trackside before being transferred to hospital.

As a result of the worsening conditions, the WSS race has been delayed until after the second World Superbike race to be held at 12.30GMT.

Kenan Sofuoglu starts from pole position and is joined on the front row by Sam Lowes and Vladimir Leonov.