He's gone 0.7s clear of teammate Sainz at the top of the timesheets. Impressive.
He's within a tenth of Leclerc's top time.
Further down, Magnussen moves up to fourth.
He goes second, a tenth off Leclerc.
A 1m34.898s for Leclerc, 0.425s clear of Perez. Norris and Piastri complete the top four for McLaren.
He's 0.3s ahead of Bottas in the Alfa Romeo.
Hulkenberg completes the top three currently.
The first part of qualifying is underway as the two Haas cars take to the track.
According to the FIA, there's a 30 per cent chance of rain.
Five-place grid penalty for Stroll for overtaking under yellow flags in FP3.
For "allegedly overtaking under yellow flags" - if found guilty, it's surely a grid penalty.
Over an hour until qualifying kicks off in Las Vegas.
We will be building up to it shortly!
Russell on top ahead of Piastri and Sargeant.
The session has been halted.
Replays show him clouting the barrier. His rear-left wheel has come off.
He's returning slowly back to the pit lane.
A 1m34.093s for Russell, 0.3s ahead of Piastri.
Perez improves to fourth overall.
Piastri, Russell, Sargeant, Verstappen, Albon, Alonso, Perez, Bottas, Magnussen and Hamilton.
Piastri goes fastest now for McLaren as Sargeant slots into third.
He's just a tenth off Russell's top time.
Mercedes continue to find more time as Russell sets a 1m34.585s, 0.068s ahead of Verstappen.
Perez, Alonso and Bottas complete the top five.
Russell goes fourth, while Hamilton only manages seventh. Not great considering new tyres and a better track.