Ferrari has traced the cause of Sebastian Vettel's crash in testing to damage caused to the wheel rim by a foreign object.

The German went off track at the beginning of Turn 3 on Wednesday, a corner which has become flat out since the current cars were introduced in 2017.

Footage revealed the front-left of Vettel's car dropped down moments before going off, hinting at a mechanical issue and that has now been confirmed.

"After thorough checks, we found that Seb’s off yesterday was due to a (wheel) rim issue," said Ferrari in a statement.

"The rim had been damaged a few seconds before by an impact with a foreign object."

That will be of relief to the Italian team as the discovery of a fundamental issue with the car at this stage of pre-season testing would have been very hard to solve before Australia.

As it is, Charles Leclerc has continued as normal on Thursday, setting a new fastest time for testing so far, a 1m16.231s.