Sebastian Vettel says he was 'shocked' to see the barriers lifting up and over the Toro Rosso of Carlos Sainz after the youngster crashed in FP3 for the Russian Grand Prix.

The Spaniard lost control of his car under braking for turn 13 at the Sochi Autodrom, striking the near-side wall before spearing into the barrier nose-first. Taken to hospital - where he will be kept in overnight -, though Sainz escaped injury, many have expressed concern by the way he was trapped in his car by the flexible TecPro barriers coming up and over him.

By shifting up, the flexible barriers, which are partially packed with foam to disperse energy in an impact, failed to prevent Sainz's Toro Rosso from going through and spearing the Armco behind them, while cranes were required to lift the TecPro off his car before he could be extricated.

With the issue set to be raised in the drivers' briefing, Vettel admits he is worried by the way the barriers reacted to the impact, saying it is important now for the FIA to understand whether it is a flaw of the barrier or an error in the way they have been installed.

"It was shocking to see that he was so deep into the barriers - and covered by the barriers - so if you look at the accident of Max [Verstappen] in Monaco and compare it to Carlos' accident, it is very different the way the barriers worked.

"That it something we need to understand because the idea is for the barriers not to come on top of you or for the car to go under the barriers. It is something we need to understand because it took longer [to extricate him] because of that.

"I don't know why, if there was anything wrong with the way they installed the TecPro barriers or if it was just coincidence the way that he crashed, but for sure that is something that needs to be avoided."

Though Sainz has expressed a desire to race and has been given the provisional all-clear by FIA stewards, Vettel warns against him coming back too soon.

"Obviously it would be great to have him with us tomorrow but, after such heavy impacts, I think we need to be patient. I remember Sergio Perez having an accident and wanting to start the day after, but then he couldn't even start the grand prix after that one, so I think it is wiser to take the time."