The world of Formula One has paid tribute to former medical delegate Sid Watkins who died on Wednesday night at the age of 84.
Watkins was the on-track surgeon for 26 years from 1978 through to 2004, with his crusade to improve medical facilities in Formula One helping to dramatically cut the number of deaths and serious injuries in the sport.
Throughout his career in F1, Watkins' actions helped save the lives of Northern Ireland's Martin Donnelly, Finland's double world champion Mika Hakkinen and Austrian Gerhard Berger, among others.
Confirming Watkins' passing, McLaren Group chairman and close friend Ron Dennis said: "Today the world of motor racing lost one of its true greats.
"No, he wasn't a driver. No, he wasn't an engineer. No, he wasn't a designer. He was a doctor and it's probably fair to say he did more than anyone, over many years, to make Formula One as safe as it is today.
"Many drivers and ex-drivers owe their lives to his careful and expert work, which resulted in the massive advances in safety levels that today's drivers possibly take for granted."
Watkins was a well-known and highly respected figure in motor sport, with drivers and fans alike expressing their sadness on Twitter.
Rubens Barrichello, an F1 veteran for 19 seasons, said: "It was Sid Watkins that saved my life in Imola 94.great guy to be with,always happy...tks for everything u have done for us drivers.RIP."
Compatriot Bruno Senna, whose uncle and three-time world champion Ayrton was tended to by Watkins following his fatal crash at the 1994 San Marino Grand Prix, added: "RIP Prof. Sid Watkins. Sad news for us who stay behind."
Watkins worked tirelessly to improve safety in the cockpit, on the track, and the medical support at circuits alongside the likes of Britain's triple world champion Sir Jackie Stewart and FIA president Max Mosley.