Haas driver Grosjean flung into barriers at high speed on Friday after drain grille pops up at kerb on Turn 9
Raikkonen fastest in Malaysian GP practice after track cleared following freak crash
Kimi Raikkonen was fastest in final practice for the Malaysian Grand Prix as championship leader Lewis Hamilton again failed to trouble the front-runners.
The Ferrari duo of Raikkonen and Sebastian Vettel set the pace on Saturday morning in Sepang, with the Finn clocking an unbeatable time of 1 min 31.880 seconds.
It was not all plain sailing for Ferrari as Vettel was forced to return to his garage towards the end of the session after slowing down on track.
Hamilton had suffered what he labelled a "very difficult" day on Friday as he was unable to get within a second of Vettel, who is looking to close a 28-point gap in the drivers' standings to the Mercedes man.
It improved only slightly for Hamilton, who was fifth fastest, with his teammate Valtteri Bottas ahead in fourth.
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The Red Bulls could also threaten Hamilton's hopes of a strong qualifying - both were fast in Friday's running and Daniel Ricciardo was the man who got closest to the Ferraris again.
The second Red Bull of Max Verstappen was sixth fastest despite a late collision with Renault's Jolyon Palmer.
The Force India pair of Sergio Perez and Esteban Ocon sandwiched eighth-place Felipe Massa and Stoffel Vandoorne's McLaren rounded out the top 10.
Fernando Alonso was next in the sister McLaren with Lance Stroll's Williams ahead of the Haas of Kevin Magnussen.
Renault's Nico Hulkenberg was 14th, with Carlos Sainz and Pierre Gasly next up in the Toro Rossos, Palmer only able to take 17th before his late coming together with Verstappen.
Romain Grosjean had suffered a big crash on Friday after his Haas hit an uncovered drain and the Frenchman was 18th in final practice ahead of the Sauber duo of Marcus Ericsson and Pascal Wehrlein.
Grosjean's freak crash
Formula One inspectors have given the Sepang circuit the all-clear, race organisers said on Saturday, after a loose drain caused a shocking tyre explosion during Malaysian Grand Prix practice on Friday.
Romain Grosjean's Haas was flung into the barriers at high speed on Friday after a drain grille, which should have been welded down securely, popped up at a kerb on Turn 9 after Kimi Raikkonen's Ferrari drove over it.
"All drain covers were inspected last night. It was reinforced - double checked, triple checked," the Sepang circuit's chief executive Razlan Razali told AFP on Saturday.
"If FIA do not say anything the race is good to go. We only listen to the FIA," he added ahead of Saturday's final practice and qualifying sessions.
Watch the crash
In the freak incident, Grosjean's car spun after he hit the raised metal drain cover at more than 200 kilometres per hour causing huge damage to his Haas.
The impact instantly ripped his right rear tyre from its rim and sent the out-of-control car careering into the safety barriers with an impact estimated at 17G - or 17 times the force of gravity.
Following the Frenchman's crash, safety officials spent Friday evening checking every drain cover at the 5.543km circuit.
"All drain covers were inspected last night. It was reinforced, double checked … triple checked," Razlan said, adding that there had been an FIA inspection earlier in the week which had declared the track safe.
"On Thursday, the FIA did a track inspection. We got a clean go to race," he said.
The FIA stewards at Sepang gave Haas special permission to repair Grosjean's car due to the unusual nature of the incident.
Under F1 rules, teams must normally observe a strict overnight curfew, during which they are not permitted to work on their cars.
Officials said in a statement that it was because they "consider that the circumstances causing the crash of Car 8 were entirely and clearly beyond the control of the Driver and the Competitor".
It came after an angry Haas team principal Guenther Steiner slammed the state of the track.
"Thank God he didn’t get hurt or anything," he said on Friday.
"The car is damaged, in my opinion, things like this in 2017 shouldn’t happen on a permanent circuit, they shouldn’t happen on any circuit. This is, in my opinion, not acceptable. This is not up to the standards."