The reigning world champion ended up 0.768s clear of teammate Sergio Perez as Red Bull blew away the opposition around the revised, faster Circuit de Barcelona-Catalunya, which has had its final chicane removed. 

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Esteban Ocon impressed to sit just over eight tenths adrift of Verstappen’s searing pace in third, ahead of Nyck de Vries who caught the eye in his AlphaTauri, and Alpine teammate Pierre Gasly. 

Aston Martin’s Fernando Alonso was the only other driver to get within a second of Verstappen’s FP1 benchmark. 

Kevin Magnussen was a surprise seventh for Haas, ahead of the upgraded Ferraris of Charles Leclerc and Carlos Sainz, who ended up a tenth slower than his teammate despite running their new sidepods on his SF-23. 

Ferrari conducted a back-to-back with Leclerc sticking to their old-spec sidepods and Sainz debuting the revised design.

In what is set to be a crucial weekend for Mercedes to get a true read of their heavily-updated W14 challenger, George Russell could only set a time good enough for 10th, over a second off the pace. 

Seven-time world champion Lewis Hamilton was a further tenth back in 12th, with the Mercedes duo split by McLaren’s Lando Norris. 

There was a near-miss for Logan Sargeant in the closing stages of the opening session as the Williams driver made light contact with Gasly’s Alpine.