Formula 1 leader Oscar Piastri showed impressive speed in sole practice for the Belgian Grand Prix on Friday with Max Verstappen starting Red Bull's new era by denying champions McLaren the one-two.
Piastri set a laptime of 1:42.022 on soft tyres, a hefty 0.404 seconds quicker than four-time world champion Verstappen whose team are racing without Christian Horner in charge for the first time since they entered the sport in 2005.
McLaren's Lando Norris was third on the timesheets, 0.504 seconds off the pace and with work to do if he is to reduce Piastri's eight-point lead.
With Belgium running to the sprint format, qualifying for Saturday's 100km race replaces the usual second Friday practice session.
Mercedes George Russell, who won last year before being stripped of victory for an underweight car, was fourth fastest with teammate Kimi Antonelli sixth and separating the Ferraris of Charles Leclerc and Lewis Hamilton.
Canadian Lance Stroll was eighth for Aston Martin with teammate Fernando Alonso ninth and Racing Bulls' Isack Hadjar completing the top 10 as his former boss Laurent Mekies started work as Horner's replacement.
Horner was dismissed after this month's British Grand Prix at Silverstone.