Red Bull and world champion Max Verstappen were kept out of the top three by Logan Sargeant, who put in a terrific lap on his home circuit in FP3.
FP3 was curtailed by five or so minutes, with the session red-flagged after Alex Albon lost a wheel on his Williams.
Mercedes' George Russell and McLaren's Oscar Piastri showed solid pace and finished FP3 first and second respectively.
Lewis Hamilton struggled to make improvements on his previous two practice sessions, only going eighth quickest.
With practice now over, attentions will now turn to what promises to be an enthralling qualifying session later on Saturday.
Here are the timesheets from all the practice action on the strip.
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Las Vegas Grand Prix FP3 results - Saturday November 18th
1. George Russell (Mercedes): 1:34.093
2. Oscar Piastri (McLaren): +0.398
3. Logan Sargeant (Williams): +0.552
4. Max Verstappen (Red Bull): +0.560
5. Sergio Perez (Red Bull): +0.613
6. Alex Albon (Williams): +0.633
7. Fernando Alonso (Aston Martin): +0.695
8. Lewis Hamilton (Mercedes): +0.760
9. Valtteri Bottas (Alfa Romeo): +0.815
10. Kevin Magnussen (Haas): +0.974
11. Lando Norris (McLaren): +0.996
12. Nico Hulkenberg (Haas): +1.019
13. Lance Stroll (Aston Martin): +1.160
14. Esteban Ocon (Alpine): +1.204
15. Zhou Guanyu (Alfa Romeo): +1.788
16. Charles Leclerc (Ferrari): +1.815
17. Carlos Sainz (Ferrari): +1.846
18. Yuki Tsunoda (AlphaTauri): +1.994
19. Pierre Gasly (Alpine): +2.392
20. Daniel Ricciardo (AlphaTauri): +3.685
Las Vegas Grand Prix FP2 results - Friday November 17th
1. Charles Leclerc (Ferrari): 1:35.265
2. Carlos Sainz (Ferrari): +0.517
3. Fernando Alonso (Aston Martin): +0.528
4. Sergio Perez (Red Bull): +0.820
5. Valtteri Bottas (Alfa Romeo): +0.864
6. Max Verstappen (Red Bull): +0.918
7. Nico Hulkenberg (Haas): +1.224
8. Lance Stroll (Aston Martin): +1.231
9. Lewis Hamilton (Mercedes): +1.398
10. Alex Albon (Williams): +1.423
11. Lando Norris (McLaren): +1.599
12. George Russell (Mercedes): +1.625
13. Kevin Magnussen (Haas): +1.652
14. Oscar Piastri (McLaren): +1.722
15. Pierre Gasly (Alpine): +1.869
16. Esteban Ocon (Alpine): +1.976
17. Yuki Tsunoda (AlphaTauri): +2.147
18. Zhou Guanyu (Alfa Romeo): +2.391
19. Daniel Ricciardo (AlphaTauri): +2.415
20. Logan Sargeant (Williams): +2.875
Las Vegas Grand Prix FP1 results - Friday November 17th
1. Charles Leclerc (Ferrari): 1:40.909
2. Nico Hulkenberg (Haas): +2.537
3. Kevin Magnussen (Haas): +3.352
4. Max Verstappen (Red Bull): +3.488
5. Esteban Ocon (Alpine): +4.456
6. George Russell (Mercedes): +4.588
7. Carlos Sainz (Ferrari): +4.915
8. Yuki Tsunoda (AlphaTauri): +4.999
9. Sergio Perez (Red Bull): +5.884
10. Valtteri Bottas (Alfa Romeo): +6.238
12. Lewis Hamilton (Mercedes): +7.604
13. Daniel Ricciardo (AlphaTauri): +7.741
14. Zhou Guanyu (Alfa Romeo): +7.913
15. Lando Norris (McLaren): +8.038
16. Lance Stroll (Aston Martin): No Time Set
17. Oscar Piastri (McLaren): No Time Set
18. Alex Albon (Williams): No Time Set
19. Fernando Alonso (Aston Martin): No Time Set
20. Logan Sargeant (Williams): No Time Set
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