SEPANG, Malaysia: Ferrari driver Sebastian Vettel set the fastest time in the second practice for the Malaysian Grand Prix on Friday.
Mercedes drivers Lewis Hamilton and Valtteri Bottas struggled with grip and went off track into the gravel within moments of each other.
Bottas’ left wheel locked as he came out of Turn 10. Hamilton, out of Turn 7, skidded sideways and then backward into the dirt.
Hamilton was sixth and Bottas seventh.
Kimi Raikkonen was second to give Ferrari a confidence boost ahead of qualifying on Saturday.
The session was stopped with 20 minutes remaining when Haas driver Romain Grosjean went into the barriers at full speed after clipping a loose drain cover with his left tire and flying across the track.
He climbed out unharmed. The tire was shredded. His car was towed away. Race director Charlie Whiting inspected the damage made by the loose drain cover.
Whiting and another official from motorsport governing body FIA spent several minutes examining other drain covers on the track. Whiting said shortly after that some welding came loose.
“One drain grate has come up. It just seems that it has broken away,” said Whiting, explaining that further checks would be made on other drains during the evening. “We have to get it fixed for tomorrow, of course.”
Grosjean seemed to take it in his stride.
“I didn’t see anything. Next thing I knew I was spinning and heading for the wall,” the French driver said. “I am good. I am fine, that is the most important thing.”
But it could have been much more serious, with images showing the drain cover sticking up at an angle before Grosjean clipped it.
Renault driver Jolyon Palmer and Toro Rosso’s Carlos Sainz Jr. — who is replacing Palmer next year — also went off the Sepang track, which is hosting its final race.
There was a heavy downpour before the first practice, but the track had largely dried out by the afternoon.
There is a third and final practice on Saturday before qualifying.
Hamilton has won the last two races and holds a 28-point lead over Vettel, who crashed from pole position in Singapore two weeks ago.
Earlier, in first practice, Max Verstappen posted the fastest time, followed by Red Bull teammate Daniel Ricciardo.
Vettel and Hamilton were fifth and sixth respectively.
Vettel and Raikkonen fastest in 2nd Malaysia GP practice
Vettel and Raikkonen fastest in 2nd Malaysia GP practice










