Toro Rosso to investigate Hartley's "unexpected" suspension failure

Toro Rosso's technical director James Key confirms that his team will investigate Brendon Hartley's suspension following his spin at the weekend.

The Toro Rosso technical director revealed that the suspension component that failed on the car was not a new specification.

The team chose to go back to an even older spec version for both of their cars, as a precaution.

In Saturday morning's free practice session, Hartley's left-front suspension failed and consequently made the Toro Rosso driver spin out and he ended up in the barriers.

The team called his team mate Pierre Gasly into the pits and changed his suspension, knowing the same thing could have happened to the Frenchman.

"The component that we had the issue with was not a new spec," Key said to Motorsport.com.

"As precaution we went back to a previous spec of one part, even though it wasn't associated with the failure that we had.

"The only reason we went back was only as an absolute precaution, let's take any unknowns away, even though it didn't appear to be associated with the failure."

Key admitted the failure was unexpected as the team have never experienced this failure in the past.

"It is still being investigated and understood," Key said.

"We've never had any issues at all, certainly not of that nature.

"We did nine races without any problems.

"Yes, we had some trackrod damage in Austria, but most people damaged their cars, and we had a particularly horrible thump on one of those kerbs.

"We haven't seen anything like that, all the loads that were going through the front-left suspension were well within the loads that it was designed for.: