text: LONDON, England (CNN) -- Who's the greatest driver of all-time? Michael Schumacher? Maybe Alain Prost? Ayrton Senna perhaps? In an exclusive interview with CNN, three-time Formula One world champion, Jackie Stewart had no hesitation in naming his choice for the greatest driver of all-time. 
  
  Three-time F1 champion, Jackie Stewart back in his heyday. 
  
  "My hero, and the man I most respected and probably still do is Juan Manuel Fangio." Stewart told CNN. 
  
  It's not misty-eyed nostalgia for a bygone era that persuades "The Flying Scot," as Stewart became known. And it wasn't just Fangio's tally of world titles that convinced Stewart; it is the manner in which the Argentine legend saw off his rivals. Who do you think is the greatest? 
  
  "Fangio won five world championships almost in a different car every year. He had the dignity, the style and the ability," Stewart explained. 
  
  What's more, as Stewart points out, Fangio didn't start racing in Formula One until he was 39-years-old, and whether driving a Ferrari, Lancia, Maserati or Mercedes, he kept on winning races. 
  
  Though Fangio was the greatest, Stewart rated fellow countryman Jim Clark as the best driver he raced against. 
  
  "His batting average was very good and he didn't race in too many grands prix." Clark -- who was tragically killed racing at Hockenheim in 1968 -- won 25 of his 73 Formula One races. Stewart's record is comparable, winning 27 from 100 starts. 
  
  It's this win to race ratio that really separates the good from the great Stewart believes. 