For the first time in F1 history, Friday saw four current champions from four different FIA championships take part in an official Grand Prix practice session.
Yesterday, Formula 1 world champion Lewis Hamilton was joined by 2017 WEC drivers' champ Brendon Hartley, FIA Formula 2 champion Charles Leclerc and European F3 champion George Russell in the Brazilian GP's opening session.
It doesn't get any better than that!