The FIA is inspecting drain covers around the Las Vegas Grand Prix track after the concrete frame around one failed, bringing an early end to first practice.

Carlos Sainz was running at high speed on the Strip when he approached a yellow flag, then hitting something that led to his engine switching off. The heavy impact was audible onboard, and the session was red flagged to allow for the Ferrari to be cleared. At the same time, FIA personnel went out on track to inspect the area, and soon confirmed the session would not be resumed.

“Following inspection, it was the concrete frame around a manhole cover that has failed,” an FIA spokesperson said. “We now need to check all of the other manhole covers which will take some time – we will be discussing with the local circuit engineering team about the length of time it will take to resolve and will update with any resultant changes to the schedule.”

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Multiple other teams then reported damage caused by a suspected loose drain cover, with Alpine stating it will have to replace Esteban Ocon’s chassis as a result.

The incident marks the second time in five races that a track has been deemed to be in an unsafe condition, with updated curbs in Qatar causing damage to tires that led to a change of track layout and mandated maximum stint lengths last month.

The 2019 Azerbaijan Grand Prix also saw a drain cover failure that damaged George Russell’s Williams, canceling that session at a similar stage. After checks and repairs, a second practice was able to take place on time.