Verstappen and Norris in the mix as Ferrari set pace in sole Austin practice

Max Verstappen and Lando Norris could barely be separated at the end of a sole practice session for the United States Grand Prix in which Ferrari duo Carlos Sainz and Charles Leclerc had the edge.

Three-time F1 champion Verstappen and title rival Norris were split by just 0.013s in third and fourth on the timesheet in Austin, albeit a quarter-of-a-second behind Sainz, who finished 0.021s clear of Scuderia team-mate Charles Leclerc. 

It proved to be a fascinating hour, and a crucial one for many, given the level of upgrades on the car, especially McLaren as the team unveiled a raft of updates on its MCL38s in a bid to strengthen its grip on the constructors' title race.

The cars were sporting changes to the front wing, front and rear suspension and the front brake ducts. There was additional focus on improving cooling, with specific modifications made to the brake ducts, along with a revised beam wing to reduce drag.

As for its main rival, Red Bull, its RB20s were sporting a new floor, seemingly representing a last hope for the team to make gains on McLaren given the fast-and-furious finish to the season with six grands prix in eight weekends.

Thrown into the mix was a resurfaced track, leading to a degree of twitchiness throughout the field, although there were reports of bumps and the bottoming of cars, particularly through Turn 4.

By the midway point of the session, Leclerc and Sainz were out in front following the early hard-tyre running, with the former setting a 1:34.966s, with the Spaniard a quarter of a second adrift. On a hard-tyre run a few minutes later, Sainz posted a 1:34.717s.

When it came to switching to soft tyres, Red Bull was the first to show its hand. The upshot was a 1:33.855s from Verstappen, whilst his team-mate Sergio Peresz was a disappointing 0.862s adrift, slower than Sainz on the white-striped rubber.

A second run from Perez saw him improve but only by a tenth of a second. Ultimately, the Mexican would finish a wretched 16th.

It was not until the final 10 minutes that the field commenced their qualifying simulation runs, with sprint qualifying following later in the day, and it appears as if Ferrari will be the team to beat.

With McLaren trialling a new front wing, Norris was sent out for his main soft-tyre burst with the left-hand side of his car smothered with flo-viz paint, suggesting the team has plenty of work to do to understand the new component.

Norris eventually finished a third-of-a-second clear ahead of team-mate Oscar Piastri, who endured a hair-raising moment late on when he missed the entry to the pit lane and was forced to carry on.

Lewis Hamilton in a Mercedes also sporting a plethora of upgrades was sixth quickest but that was not without its moments as he suffered a wild spin on his high-speed approach into Turn 4 that opens up into the sweep of corners that represent a hallmark of the track.

The seven-time F1 champion performed superbly to catch the slide and continue on, with the only damage sustained being to a set of hard tyres.

Just under a minute later, team-mate George Russell endured his own moment through Turn 4, albeit less dramatic. However, worse followed for the Briton as he spun out of Turn 1, resulting in him rolling backwards down the hill that follows before resuming.

Russell was seventh quickest, 0.130s slower than Hamilton, with Haas' Kevin Magnussen, Fernando Alonso in the Aston Martin and RB's Yuki Tsunoda completing the top 10, the latter 0.711s off Sainz's leading time.

Team-mate Liam Lawson, on his return to F1 after taking up the second RB seat following the departure of Daniel Ricciardo, was 13th, 0.130s behind the Japanese.

Lawson goes into Sunday's grand prix knowing he will start at the back of the grid due to a raft of power unit penalties.