Rob Smedley believes Force India was wrong to leave Sergio Perez out on track when he had been suffering from a brake issue.

Perez and Felipe Massa collided heavily at the end of the Canadian Grand Prix, with both drivers requiring precautionary trips to hospital due to the size of their respective impacts. Perez was given a five-place grid penalty for the incident and Smedley explained what he had said to the stewards as he felt Force India should have told Perez to back off.

"I showed them all the evidence," Smedley said. "I showed them the data from that lap and from the lap before. Felipe - at high speed because he's well in to the tow - brakes about five minutes earlier than the lap before. We showed them evidence from the side shot where if you take Felipe and Sebastian [Vettel] through the braking phase the distance between them is exactly the same and you see that Perez is backing towards Felipe.

"We showed them the overhead shot where Perez ... first of all he brakes very, very early, which you can see from the side view. Second of all, when he brakes the car ... either he jinks it to the left or because of the brake problems it jinks to the left, I don't know.

"And we showed them evidence from the radio transcript - which I think was around lap 67 - talking about 'we have no rear brakes'. 'I've got no rear brakes' I think was his comment, and they said 'Well if you can carry on, carry on, and if you can't, pit', which says to me it's a fairly f*****g terminal problem to be honest. Why you leave a car out when you've got that sort of problem is beyond me."

And Smedley said there had been other examples during the race of teams putting safety first with similar issues.

"You saw two teams - one of which was ours - knowing when to call it quits. With Valtteri [Bottas], we had to tell him to back off saving brakes and saving engine - more critically brakes because it can be dangerous - we had to back him off and we had to lose points, that's life.

"Lewis Hamilton - because of his problem which was brakes and engine again - had to stop the car. A guy who is fighting for the world championship and he had to stop the car, so I am a bit peeved to say the least that this has happened."