Not only was Verstappen the quickest in challenging, sandy conditions, but the Dutchman also lapped the circuit more than anybody else in his Red Bull RB16B, whilst multiple drivers lost precious track time through car issues.
Valtteri Bottas managed just six laps with a gearbox issue in his Mercedes, while Mick Schumacher's morning running was derailed by a similar problem with his Haas.
Aston Martin's Lance Stroll also saw his track time reduced by an electrical problem, whilst Lewis Hamilton, Norris and Leclerc also suffered issues.
Here, GPFans Global brings you lap and kilometre count across the day, notably highlighting the amount of track running lost by Mercedes compared to its rivals.
Drivers' lap count - pre-season testing day one
1. Max Verstappen [Red Bull] - 139 laps - 752.268km