Formula 1's United States Grand Prix looks poised to be a multi-team fight for victory based on how the top four teams have started at Austin.
Here are the early clues about the pecking order, with single-lap and long-run pace trends painting very different pictures.
Why it's so close
The combination of the varying strengths of the leading cars and the wide range of corner speeds of the Austin circuit that tests every facet of a car means that Ferrari, Red Bull and Mercedes, which were separated by less than two tenths on single-lap pace, all excelled and struggled at different parts of the track.
Pacesetter Charles Leclerc was strongest in the slow corners. He carried the highest minimum speed at Turn 1, matched Kimi Antonelli's best at Turn 12, and braked late for the Turn 11 hairpin without compromising his exit. He was often first back on the throttle.
In the high-speed sections, Leclerc was quickest through Turns 6-7, keeping part-throttle where Max Verstappen lifted - however, at times the picture in the fast corners was muddied by deployment variations. As always, the Ferrari lost significant time on the straights - just over six tenths relative to Verstappen.
Verstappen's Red Bull was mighty on the straights, gaining around six tenths on Leclerc once the speeds had settled, and a little over a tenth compared to the Mercedes. That characteristic also gave him a strong start to the lap down the start/finish straight. He was committed on the brakes in terms of stopping power, but was often later on the throttle at slow-corner exits, with that approach paying off at Turn 20, where he had a strong exit.
Where Red Bull is lacking most for Verstappen was obvious after a pretty good day left the four-time F1 world champion seeking a finer balance rather than anything drastic.
"It's clearly the low-speed performance that we are focused on at the moment," was Red Bull technical director Pierre Wache's verdict when asked by The Race if there was a standout area to improve overnight.
"Low speed is the key for us."
That aforementioned Verstappen preference for braking slightly earlier, but harder, to prioritise a good exit was clear throughout the lap but, other than at Turn 20, it did not really manifest in laptime due to the Red Bull seemingly lacking rotation.
Verstappen's Turn 1 was the worst of the top three. Despite braking earliest he was slowest back to full throttle - due to some wheelspin he had to manage - and swung from just over a tenth up on Leclerc to 0.25s behind.
Turn 12 was his other big loss, around 0.2s again. Despite again braking earlier, Verstappen did not have the response he needed when he initially started applying steering lock into the corner and ran a little deep, dropping his minimum speed 10km/h below Leclerc's and Antonelli's.
It's possible the Red Bull is not quite as compliant on the bumps in the braking zones here, which is contributing to Verstappen braking slightly earlier and not being as attacking or as confident on entry, or as steady on exit.
"Finding the right balance was more difficult than expected," Wache admitted.
Where Mercedes and McLaren fit in
Antonelli's Mercedes had a more balanced performance profile: quicker on the straights than the Ferrari but not at Red Bull level, but showing good speed on the approach to the hairpin. Potentially, that reflected differences in deployment.
He was strong in Turns 8-9, Turn 15 and Turn 12, but did lose out in several corners on the exits.
McLaren's single-lap pace also looked nowhere on the timesheets, with Lando Norris the faster of its drivers in FP2 but 1.082s off the pace. However, this time was set on hards as he had to abort both of his qualifying simulation laps.
The first was because of a snap mid-corner at Turn 9, possibly the result of running in turbulent air caused by George Russell's Mercedes ahead. His second lap, on soft Pirellis now past their best, was abandoned after a lockup at Turn 15.
"We set a purple [fastest sector time] in FP2 as well, we just didn't finish the lap," said McLaren chief technical officer Rob Marshall. "It was a competitive lap up until the point where we made a mistake.
"Going forward from here we've got to be quite optimistic really."
That first sector time was the fastest at the time he set it, and although it was eclipsed by Verstappen that was only by 0.015s - and it was faster than anything achieved by Ferrari or Mercedes.
How the long runs look
On the raw numbers, Norris's McLaren was fastest on the long-run averages in FP2, but it's a confusing picture for a number of reasons.
Austin Friday long run pace
Norris 1m41.289s (9 laps, hard)
Verstappen 1m41.481s (11 laps, soft)
Leclerc 1m41.503s (15 laps, soft)
Antonelli 1m41.521s (12 laps, medium)
Russell 1m41.602s (6 laps, medium)
Hamilton 1m41.949s (6 laps, soft)
Piastri 1m41.997s (7 laps, soft)
Hadjar 1m42.031s (10 laps, medium)
Traffic affected a number of drivers' long runs and all three tyre compounds were used, so it's tricky to compare a nine-lap Norris run on durable hards to Verstappen's 11-lap soft-tyre run, for example.
But Norris's strong long run backs up McLaren looking stronger than the FP2 result suggested.
Pirelli expects the hard tyre to "play only a limited role in defining race strategies", with a one-stop using the softs and mediums most likely.
Verstappen's soft tyres held up impressively well with consistent laptimes and less of a drop-off compared to Leclerc's.
Team-mate Isack Hadjar was clearly not as comfortable. He struggled with overheating front tyres all day; "it's just a disaster" he said of his soft tyre lap.
"It was just undriveable, and I was losing the front end massively. We need to have a look because that's not normal, why there is so much deg on one lap."
Hadjar said his tyres were "completely killed" in the high-speed corners. Red Bull's Wache said this was key to the difference as he said Hadjar and Verstappen weren't far apart on set-up.
Lewis Hamilton, George Russell, Oscar Piastri and Hadjar all appear to have started the weekend a step behind their respective team-mates.
Hamilton said he "tried a different direction with the set-up, but I wasn't comfortable in the car, especially over the bumps", while Piastri's long run pace on the softs appeared to sharply tail off.
That picture may alter as teams learn overnight lessons and change set-up and deployment patterns, but right now all four teams look like they are in the hunt at Austin.