McLaren pair Jenson Button and Lewis Hamilton have expressed their sadness and gratitude to Formula 1 safety and medical delegate Professor Sid Watkins, who died at the age of 84.
The world-renowned English neurosurgeon passed away after more than 30 years within the sport.
Button wrote on Twitter: "Rest in peace Sid Watkins. Motorsport wouldn't be what it is today without you. Thank you for all you've done, we as drivers are so grateful."
Hamilton also tweeted: "It's a sad day, with the loss of Professor Sid Watkins. Without his incredible contribution to the sport, our lives as drivers would be a risk. My condolences go out to his family."
Watkins, who saved the lives of a number of high-profile motorsport drivers, was a close friend of late three-time champion Ayrton Senna.
