Charles Leclerc led a Ferrari one-two in a heavily delayed but ultimately trouble-free Practice 2 at the Las Vegas Grand Prix.
With the lights going green at 2:30am local time after all the drain covers and water valves had been secured, drivers finally got their first proper look at the new street circuit on and around the Strip.
Turns 7, 12 and 14 proved the main action areas due to lock-ups as several took to the run-off areas.
Lando Norris had a brief scare when his car entered 'Limp Home' mode but he was able to return to the pits and reset the problem.
Ferrari managed to repair Carlos Sainz's car after the hefty damage caused by the loose water valve in the first session, with the Spaniard showing strong pace as most used soft tyres.
Max Verstappen went fastest on mediums before heading out on fresh softs for the qualifying runs.
Multiple drivers took turns to sit in P1 with lap times falling dramatically as grip improved every lap.
Several teams opted to use two new sets of softs as teams had extra tyres following the early end to FP1.
The Ferraris upped the ante on their second set with Leclerc claiming P1 on a 1m35.265s, almost half a second clear of teammate Sainz.
The Monegsque even had time for a small tussle with Verstappen as the pair went side-by-side down the Strip and through the chicane section.
Fernando Alonso improved to sit a hundredth behind his fellow countryman in third, while street circuit specialist Sergio Perez was the lead Red Bull in fourth.
Valtteri Bottas was a strong fifth for Alfa Romeo, as Verstappen only managed sixth after being one of the earlier drivers to switch onto high fuel runs.
Nico Hulkenberg took seventh running the old-spec Haas, ahead of Lance Stroll in eighth.
Lewis Hamilton was the fastest Mercedes in ninth as Alex Albon completed the top 10 for Williams.
McLaren had a subdued session with Lando Norris 11th and Oscar Piastri 14th, split by George Russell and Kevin Magnussen in 13th.
Pierre Gasly and Esteban Ocon were 15th and 16th for Alpine, followed by Yuki Tsunoda and Zhou Guanyu. Daniel Ricciardo and Logan Sargeant completed the order.