Formula 1 championship leader Lando Norris set the pace in second practice at the Las Vegas Grand Prix, a significant portion of which was lost to two red flags at the end of the session.
The first of them - shown so race control could investigate the possibility of a manhole cover being loose before the final corner, which could not be confirmed with the use of CCTV - wiped out more than a quarter of the session and left just six minutes on the clock when the session resumed.
And a second red flag that ultimately brought FP2 to a premature end was shown soon after the restart for track maintenance, relating to the same manhole cover issue.
The timing of those stoppages made the order particularly difficult to read, too - as the first fell at an awkward time in the middle of most drivers' qualifying simulation runs, and the second came soon enough after the restart that no driver was able to set a subsequent laptime.
Norris's 1m33.602s was nevertheless the fastest time of the weekend so far, his McLaren - which again had a misadventure up the escape road at Turn 12, as it did in FP1 - ending the session 0.029s ahead of Mercedes' Kimi Antonelli.
Charles Leclerc was fastest on the initial medium-tyre runs and was third in the final classification, but he parked up after exiting the pits but before the second red flag was shown, reporting that "something broke" on his Ferrari's gearbox.
Leclerc had earlier just about avoided nosing into the barrier at Turn 9 when he ended up on a compromised line through the preceding corners.
Nico Hulkenberg (Sauber) and Racing Bulls duo Isack Hadjar and Liam Lawson all got representative laps in on the soft tyre before the red flag to end up fourth, fifth and sixth, Hadjar having a noteworthy moment at Turn 12.
FP2 times
1 Lando Norris (McLaren) 1m33.602s
2 Kimi Antonelli (Mercedes) +0.029s
3 Charles Leclerc (Ferrari) +0.161s
4 Nico Hulkenberg (Sauber) +0.277s
5 Isack Hadjar (Racing Bulls) +0.291s
6 Liam Lawson (Racing Bulls) +0.299s
7 George Russell (Mercedes) +0.435s
8 Alex Albon (Williams) +0.465s
9 Max Verstappen (Red Bull) +0.503s
10 Lewis Hamilton (Ferrari) +0.525s
11 Lance Stroll (Aston Martin) +0.589s
12 Pierre Gasly (Alpine) +0.771s
13 Carlos Sainz (Williams) +0.833s
14 Oscar Piastri (McLaren) +0.891s
15 Yuki Tsunoda (Red Bull) +1.090s
16 Franco Colapinto (Alpine) +1.222s
17 Ollie Bearman (Haas) +1.384s
18 Fernando Alonso (Aston Martin) +1.410s
19 Esteban Ocon (Haas) +1.626s
20 Gabriel Bortoleto (Sauber) +1.897s
