Mercedes delivered an eye-opening final practice session to tee themselves up for a shot at a potential front-row lock-out for the Mexico City Grand Prix.
George Russell spearheaded a team one-two, posting a time of one minute 18.399s, finishing 0.144s clear of Lewis Hamilton and with Red Bull's Max Verstappen almost half-a-second back.
Trackside engineering director Andrew Shovlin remarked prior to FP3 that the team felt the Autodromo Hermanos Rodriguez would be an ideal track for the car's chassis.
That is due to the fact the high altitude in Mexico means the drag penalty Mercedes has carried at numerous other circuits this year is less of an issue here.
It was naturally a more representative session given what transpired in Friday's two runs, notably with regard to FP2 which was predominantly given over to Pirelli's prototype tyre test.
Russell ended the day with the fastest time of 1:19.970s but just 10 minutes into FP3, Carlos Sainz surpassed that by a tenth of a second before the Briton then set what appeared to be a benchmark time of 1:19.405s.
But around 15 minutes later, and on his first flying lap, Verstappen again underlined why the RB18 is the class act of the field this year as he edged ahead of Russell by 0.109s, even bemoaning his first sector after hitting the kerbs.
On his second run, Verstappen extended his advantage over Russell to 0.287s but on a fresh set of soft tyres, the latter set his explosive time of 1:18.399s, going fastest in the first and third sectors, leaving the Dutchman seven-tenths adrift.
Moments later, he was followed over the line by Hamilton who finished 0.144s shy of his team-mate, and seemingly with more to come after losing three-tenths to Russell in the final sector.
On his own fresh set with 15 minutes remaining, Verstappen was 0.029s down in the first sector when he locked the inside wheel at turn four and immediately backed off.
After ramping up for a second run on the same rubber, Verstappen could only get to just under half a second behind Russell, and leaving his hopes on the line of a first pole at this track.
As for the rest of the field, Ferrari's Charles Leclerc was fourth quickest, but 0.724s off the pace, followed by home hero Sergio Perez in his Red Bull and then Sainz who finished nine-tenths down.
McLaren's Lando Norris and Valtteri Bottas in his Alfa Romeo were the only other drivers to finish within a second of Russell, the latter 0.991s adrift.
Ninth-quickest Yuki Tsunoda in his AlfaTauri was a further half a second back, with Williams' Alex Albon completing the top 10.
For the likes of McLaren's Daniel Ricciardo and Sebastian Vettel in his Aston Martin, it was another difficult session, with the duo 14th and 19th respectively.
Vettel, in particular, complained of his AMR22 being a problematic in every area.
Haas' Kevin Magnussen propped up the field, 2.872s down.
Mexico City Grand Prix final practice results
1. George Russell [Mercedes] 1:18.399
2. Lewis Hamilton [Mercedes] +0.144s
3. Max Verstappen [Red Bull] +0.477s
4. Charles Leclerc [Ferrari] +0.724s.
5. Sergio Perez [Red Bull] +0.842s
6. Carlos Sainz [Ferrari] +0.902s
7. Lando Norris [McLaren] +0.918s
8. Valtteri Bottas [Alfa Romeo] +0.991s
9. Yuki Tsunoda [AlphaTauri] +1.483s
10. Alexander Albon [Williams] +1.518s
11. Esteban Ocon [Alpine] +1.561s
12. Zhou Guanyu [Alfa Romeo] +1.620s
13. Fernando Alonso [Alpine] +1.638s
14. Daniel Ricciardo [McLaren] +1.740s
15. Pierre Gasly [AlphaTauri] +1.931s
16. Lance Stroll [Aston Martin] +2.078s
17. Mick Schumacher [Haas] +2.199s
18. Nicholas Latifi [Williams] +2.449s
19. Sebastian Vettel [Aston Martin] +2.587s
20. Kevin Magnussen [Haas] +2.872s