Results at the end of the day:
1. Norris (McLaren) 1m19.568s, C4, 98 laps
2. Leclerc (Ferrari) 1m20.165s, C3, 80 laps
3. Sainz (Ferrari) 1m20.416s, C3, 69 laps
4. Russell (Mercedes) 1m20.784s, C3, 77 laps
5. Hamilton (Mercedes) 1m20.929s, C3, 50 laps
6. Vettel (Aston Martin) 1m21.276s, C3, 52 laps
7. Tsunoda (AlphaTauri) 1m21.638s, C3, 116 laps
8. Alonso (Alpine) 1m21.746s, C3, 141 laps
9. Verstappen (Red Bull) 1m22.246s, C2, 147 laps
10. Bottas (Alfa Romeo) 1m22.572s, C3, 23 laps
11. Albon (Williams) 1m22.760s, C3, 66 laps
12. Schumacher (Haas) 1m22.962s, C3, 19 laps
13. Stroll (Aston Martin) 1m23.327s, C3, 63 laps
14. Latifi (Williams) 1m23.379s, C3, 66 laps
15. Mazepin (Haas) 1m24.505s, C2, 20 laps
16. Kubica (Alfa Romeo) 1m25.909s, C3, 9 laps
Obviously it's only the first day and only a muppet would read too much into it, but it looks like Merc, Ferrari, and McLaren are in a very good position. Red Bull have cranked up the laps and don't look like they tried any fast runs so I think they're also good, if perhaps a touch behind those three. Aston Martin, Alpine, and AlphaTauri probably sitting in the midfield, with the three backmarker teams still there. Worrying for Alfa and Haas that they managed so few laps; worrying for Williams that they managed the laps but still sit so far back.