Formula One supremo Bernie Ecclestone has hailed Sid Watkins as "irreplaceable" following his death on Wednesday.
Watkins, the FIA medical delegate and race doctor for 26 years from 1978 through to 2004 after being appointed by Ecclestone, passed away after a short illness at the age of 84.
Watkins helped pioneer safety in motor sport, with his work saving the lives of a number of drivers following an accident, as well as ensuring many others avoided serious injuries.
"I am pretty sure he is irreplaceable. You only meet somebody of his calibre once in your lifetime," said Ecclestone of close friend Watkins.
"What Sid did in the way of safety in Formula One was incredible. He gave his whole life to that cause, to make sure it could be as safe as it possibly could be.
"We all owe him a debt of gratitude for his caring and commitment."
Speaking to formula1.com on the measures Watkins implemented, Ecclestone added: "When I invited him to join Formula One as its official doctor part way through the 1978 season, we discussed many aspects of safety and medical issues.
"We agreed we needed a proper hospital at the track in the form of a fully equipped medical centre to stabilise injured drivers with immediate treatment, and a helicopter to transport them subsequently to specialist facilities, and that the helicopter pad had to be as close to that trackside hospital as possible.
"Sid carried all of those things through, and many more. After the accidents to Jochen Rindt and then Ronnie Peterson, I suggested he should have a medical intervention car and he should take responsibility for taking drivers into medical care.
"We always talked things through and worked together, and he then took care of all the medical things which I knew nothing about."
Sir Jackie Stewart yesterday called for a permanent memorial in Watkins' honour "to recognise his contribution to motor sport, particularly Formula One".