Two-time world champions are a rare breed. Over the F1 decades only six have emerged: Alberto Ascari, Graham Hill, Jim Clark, Emerson Fittipaldi, Mika Häkkinen and (unless his luck changes) Fernando Alonso.
They exist in a plane above the 'singleton' champs - Hulme, Hunt, Scheckter, the Rosbergs et al - and as that roll-call attests, they're a pretty special bunch. Three have passed, Alonso races on until at least the end of 2018, Fittipaldi seems from a distant era.
But Häkkinen? Well, as the most successful Finn among many flying fellows, his presence still looms large. Michael Schumacher's defining rival; in his 1998-99 pomp, maybe the quickest of all. And, happily, very much still with us.