Williams called an end to their Barcelona test a day early on Wednesday after Nico Rosberg wrecked his car in a high-speed crash.

A team spokeswoman said the German was unhurt in the accident at turn seven of the Circuit de Catalunya but was taken to hospital in the Spanish city as a precaution before being allowed to go home.

The cause of the crash was being investigated but it happened early in the day when the track was still damp from heavy rain on Tuesday.

"Nico went off on his first run and had a crash that resulted in heavy chassis damage," said technical director Sam Michael.

"Nico's fine, however the damage cannot be repaired at the circuit so the test team is now returning to the factory."

The crash was the second this week at the circuit, which hosts the Spanish Grand Prix on May 13, for the former world champions.

Japanese test driver Kazuki Nakajima hit the tyre barriers on Monday, badly damaging the right side of the car and forcing the team to fly out more parts.