Hockenheim - Formula One's decision to delay the introduction of the long-awaited cockpit protection 'halo' device until next year was given a mixed reception by drivers on Friday.
Nico Rosberg, who was fastest for Mercedes in practice for his and his team's home German Grand Prix, said the postponement to 2018 as disappointing.
But defending champion and team-mate Briton Lewis Hamilton and rival Australian Daniel Ricciardo of Red Bull were more understanding of the dilemma facing the sport.
"It's there and it is all ready to go," said Rosberg. "It just needs to be put on the car.
"A large majority of drivers wanted to get it on the car as soon as possible.
"It just made sense as it's such a huge step in safety - so, it's disappointing to hear that it's not going to be on the car for next year."
A demonstration shown to the drivers at last weekend's Hungarian Grand Prix claimed that the halo could increase the safety of drivers by 17 percent in the case of head injuries suffered in the cockpit in accidents.
Hamilton, who was previously against the device, said he had changed his mind after seeing how the halo could give added protection.
But on Friday, he said: "If it's there, it's there. And, if it's not, it's not. It makes no difference to me.
"As we said last week, it is a safer option, but I've not driven with it - and others have said that it's kind of a claustrophobic feeling. It's kind of in the view when you are driving.
"I think what they are going to do is to try and work on improvements for the future, but we can't ignore the fact that that is a solution which will be safer for us."
Ricciardo said: "One thing we have been leaning towards is that, if there isn't a perfect solution, we should wait and get something proper rather than do it in a half-hearted way.
"So, I think that's the reason why it is postponed, for now.
"Sure if it is on the car, we want it to work in the right way, but I understand that it is new and it's not easy to get something right overnight. I respect the decision."
Earlier Friday, Red Bull team chief Christian Horner defended the decision to postpone the introduction of the 'halos' and said not enough research and development had been carried out.
Horner spoke out after drivers' union boss Alex Wurz warned that the move, taken on Thursday by the Formula One Strategy Group, had put business interests before driver safety.
"I disagree with that," said Horner. "We've agreed for a system to come in in 2018, but it needs to be fully researched, fully developed and fully tested.
"At the moment, other than a couple of installation laps from a couple of drivers, there's been no (testing) mileage put on this."
He added that new tyre compounds are always tested intensively and extensively before they are introduced and said the same rigour must be applied to safety components.
News of the rejection of the proposed cockpit protection device came just hours after four-time world champion Sebastian Vettel warned "nothing justifies death."
The Ferrari driver said: "It would be the first time in human history that we've learned a lesson and we did not change."