The ISR team has withdrawn from the Hungarian round of Formula Renault 3.5 due to chassis damage on both of its cars
Esteban Guerrieri and team-mate Filip Salaquarda will not race this weekend because the team was unable to replace both tubs at the circuit and has returned home to the Czech Republic.
"On the grounds of safety we aren't able to get out, it is as simple as that," said ISR engineer Peter Berry. "In testing yesterday they were both quick, but we can't do anything else.
"There was one tub available, but then there's the amount of work involved and you have then got to say to one of the drivers 'sorry you're not going to drive'. How do you decide that, toss a coin?"
The withdrawal will hurt Guerrieri's title charge - the Argentinean came to Hungary third in the championship after taking three consecutive wins earlier this year.
"I'm disappointed for the boys because they're fighting for the championship, we're fighting for the teams' title, and we have already given too many points away this year," Berry added.
"If you were to look at the underside of the car you would just see a little crack. [Renault Sport] won't sign off that the car is 100 per cent. They're covering themselves for safety, but I've done GP2 and F3 and I've seen worse.
"We had no choice. We're not here to make the numbers up. If you work all through the night for one car, it's possible to make a mistake or do something stupid, and we're competitors."
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