Stirling Moss was "an irreplaceable person" of the kind not often seen in motorsport, according to Emanuele Pirro.
Moss, widely considered the greatest Formula One driver never to win the world championship, died last Sunday at the age of 90.
The London-born driver finished runner-up four times and third three times between 1955 and 1961, coming closest in 1958, when he defended title rival Mike Hawthorn against the threat of a racing penalty and went on to finish just one point behind in the driver's standings.
Pirro, a five-time 24 Hours of Le Mans winner who spent three years in F1, remembers Moss as a committed racer until he was in his 80s, when he finally decided he could no longer compete.
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"Stirling Moss was such an irreplaceable person. He raced until a few years ago with historic cars," Pirro told Stats Perform.
"I witnessed his real retirement during the historic Le Mans. We were doing the official qualifying session for the race. He was an extraordinary figure in the paddock. We were in the park ferme and he told me while getting out of the car, 'That's it: I won't be racing any longer. For the first time, I was scared to race, so it is time to stop'.
"Stirling Moss never won a title, finished second four times and finished third once. The year he was close to clinching the title, it was won by Hawthorn by one point. Hawthorn was disqualified previously for entering the track in the wrong direction after spinning off. Stirling Moss fought to give the points back to his main rival because he did not want to win the title in this way. We must be happy that motorsport had this kind of people."
Former F1 driver and now broadcaster Martin Brundle saluted Moss for his success across so many disciplines at a time when motorsport was at its most dangerous.
Stirling Moss - gifted driver and British sporting icon
Despite the risks, Pirro says Moss never wanted greater safety precautions to be brought in for drivers as he felt it would have dulled the feeling of achievement at the end of a race.
"Once, I asked him about safety in F1," Pirro remembered. "He was very brave and never pushed to have a safer F1.
"He told me: 'Today's motorsport is like walking on a tight rope. In my era, you had the Grand Canyon underneath; now, there is a mattress. The difficulty of walking on the rope is more or less the same, but the challenge and the joy to get to the other side cannot be compared'."