Norris topped the timesheets with a lap of 1:42.704, three-tenths quicker than his teammate Piastri, who spent much of the session sidelined with a suspected power unit issue.
McLaren said: “We’d identified a PU issue, which we believe we’ve rectified. Now planning to get Oscar back out when we get going again.”
Piastri’s delay came at a fortunate moment as a red flag was thrown after debris at Turn 16 revealed a damaged kerb. That stoppage limited the track time of rivals and allowed McLaren to work on the car without major loss.
When running resumed, Norris stamped his authority with two strong laps, extending his margin over Max Verstappen and forcing the Red Bull driver to settle for seventh. Ferrari’s Charles Leclerc split the McLaren pair in the early stages but ultimately finished third, half a second adrift.
George Russell impressed with fourth despite illness keeping him out of Thursday’s media duties. The Mercedes driver reported over the radio that he “didn’t feel great” but still produced a competitive lap. Williams showed promise too, with Alex Albon in fifth and Carlos Sainz eighth.
Lewis Hamilton brushed a wall at Turn 5, damaging the front wing of his Ferrari before returning to the pits. He ended the session 12th and admitted: “I’ve clipped the wall.”
The closing minutes brought further drama as Verstappen and Esteban Ocon both had late moments, but Norris held firm to secure McLaren’s advantage ahead of Sunday’s race.
2025 Azerbaijan Grand Prix – Free Practice 1 F1 results (Baku City Circuit)
1. Lando Norris McLaren 1:42.704
2. Oscar Piastri McLaren +0.310
3. Charles Leclerc Ferrari +0.552
4. George Russell Mercedes +0.717
5. Alex Albon Williams +0.859
6. Yuki Tsunoda Red Bull +1.034
7. Max Verstappen Red Bull +1.086
8. Carlos Sainz Williams +1.155
9. Liam Lawson Racing Bulls +1.199
10. Isack Hadjar Racing Bulls +1.271
11. Nico Hulkenberg Sauber +1.282
12. Lewis Hamilton Ferrari +1.383
13. Kimi Antonelli Mercedes +1.409
14. Oliver Bearman Haas +1.447
15. Gabriel Bortoleto Sauber +1.460
16. Fernando Alonso Aston Martin ++1.532
17. Esteban Ocon Haas +1.735
18. Lance Stroll Aston Martin +1.822
19. Franco Colapinto Alpine +2.595
20. Pierre Gasly Alpine +2.714
The Azerbaijan Grand Prix continues on Sunday, 21 September, with 51 laps around the 6.003km Baku City Circuit.
