Daniel Ricciardo upheld McLaren's strong pre-season form on Thursday in Barcelona, the Aussie topping the morning's running thanks to a late flyer in the session.
But Ferrari's F1-75 also remained among the front runners at the Circuit de Catalunya, with Carlos Sainz clocking in second ahead of the lunch break, a few tenths behind Ricciardo.
Further adrift, AlphaTauri's Pierre Gasly concluded the morning third.
All three drivers set their fastest time on Pirelli's mid-range C3 tyre compound.
| Pos | Driver | Team | Time | Tyre | Laps |
|---|---|---|---|---|---|
| 1 | Daniel Ricciardo | McLaren | 1m20.355s | C3 | 65 |
| 2 | Carlos Sainz | Ferrari | 1m20.546s | C3 | 71 |
| 3 | Pierre Gasly | AlphaTauri | 1m20.764s | C3 | 61 |
| 4 | Alexander Albon | Williams | 1m21.531s | C3 | 47 |
| 5 | Lance Stroll | Aston Martin | 1m21.920s | C2 | 55 |
| 6 | Mick Schumacher | Haas | 1m21.949s | C3 | 66 |
| 7 | Valtteri Bottas | Mercedes | 1m22.288s | C3 | 21 |
| 8 | Sergio Pérez | Red Bull | 1m22.412s | C2 | 38 |
| 9 | Lewis Hamilton | Mercedes | 1m22.562s | C2 | 40 |
| 10 | Esteban Ocon | Alpine | 1m23.280s | C2 | 66 |
Alex Albon delivered a productive morning for Williams, the Anglo-Thai racer finishing his half-day work session in P4 just ahead of Aston Martin's Lance Stroll.
Haas was spared its opening days woes, with Mick Schumacher racking in 65 laps to set the sixth fastest time.
But there were more reliability issues in the Alfa Romeo camp, where Valtteri Bottas put only 21 laps under his belt, the fastest of which earned him a P7 in the running order.
Behind the Finn, Sergio Perez rued an apparent gearbox failure that left the Mexican's Red Bull RB18 stranded out on the track in the latter part of the morning session and resulted in the first red flag of the week.
Finally, rounding off the top ten were Lewis Hamilton, who did not leave the Mercedes garage after the deployment of the red flag, and Alpine's Esteban Ocon who, like Hamilton, had set his time on the slower C2 tyre.
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