BAKU, Azerbaijan — Charles Leclerc and Ferrari led the way in practice for the Azerbaijan Grand Prix on Friday, after the day was disrupted when a loose drain cover wrecked George Russell's Williams.

Leclerc set the fastest time of the day in the second session, beating his teammate Sebastian Vettel by 0.324 seconds. Championship leader Lewis Hamilton was third, 0.669 off the pace.

The Baku circuit is widely believed to favour Ferrari over runaway series leader Mercedes, thanks to its mix of a long straight and slow corners. It's also a track where Leclerc tends to perform well.

The Monaco driver won a Formula Two race in Baku in 2017 shortly after his father died, and also scored his first F1 points here last year in an uncompetitive Sauber.

Leclerc was also fastest in the foreshortened first session, though only he and Vettel managed to set a time before Russell's incident forced the session to be abandoned.

Russell was travelling at high speed when his Williams car hit the loose drain cover. The impact cracked the car's chassis and scattered fragments of the car's floor across the track.

Things got worse for Russell's car when it was being taken back to the pits. The truck carrying it hit a bridge and fluid from its damaged crane flowed onto Russell's engine cover. He missed the second session.

Crews of marshals worked throughout the afternoon on clearing up the debris and reattaching the drain cover, which was supposed to have been welded down, and laid cement dust to soak up the fluid from the truck. They also checked the more than 300 other drain covers around the street circuit were secure.

Azerbaijani organizers blamed "an undetectable problem beneath the fitting (of the drain cover) that only became apparent this afternoon."

The incident could put a further strain on Williams' tight budget. It's not the first time drains have caused problems, and Williams has been a victim before.

Then-Williams driver Rubens Barrichello crashed at the Monaco GP in 2010 after a cover was dislodged, and Valtteri Bottas damaged his Williams in 2016 in the pitlane in Baku.

With limited time to test setups ahead of Saturday's qualifying, teams flocked onto the circuit in the second session, but it too was disrupted.

After 15 minutes, Lance Stroll took too much speed into a tight corner and slammed into the barriers. That left his Racing Point car with a smashed front wing and suspension, and the session was briefly stopped.

More time was lost when Daniil Kvyat spun into the barriers and the car's brakes caught fire. That marked a difficult 25th birthday for the Russian, who had been struggling with a steering issue.

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