SHANGHAI, China -- Sebastian Vettel set the fastest time in final practice for the Chinese Grand Prix as Ferrari dominated the session in cold and windy conditions.
As both Mercedes appeared to struggle for grip, setting times slower than their personal bests from Friday practice, Vettel upped his pace by half a second to lead the session with a 1:33.018. Teammate Kimi Raikkonen was 0.451s adrift in second place after losing a chunk of time to his teammate in sector one and a further tenth in the final sector.
With blustery conditions throughout the session, the key to a quick time was judging how those gusts of wind would impact braking points and the balance of the car. Vettel appeared to get his quick lap spot on, but Hamilton, who had been fastest throughout Friday practice, looked out of sorts as he spun through 540 degrees on the exit of Turn 10 midway through the session and made mistakes at Turns 6 and 14 on his hot lap.
Those errors left Hamilton 1.039s shy of Vettel and 0.296s off teammate Bottas, who set the third fastest time on an ultra-soft tyre run earlier in the session. Even the Red Bull of Max Verstappen managed to get ahead of the reigning champion with a quick lap at the end on ultra-softs tyres, but Red Bull finished the session concerned rather than encouraged after Daniel Ricciardo suffered an engine failure with 25 minutes remaining.
"I think we've got a suspected turbo failure, that's what the analysis is at the moment," team boss Christian Horner said. "Whether that's damaged the combustion engine as well only time will tell. It certainly looks turbo orientated at the moment.
"It's the second race in a row. We had the energy store last race, we've got this issue before we've even got into qualifying here and we're on race three so disappointed is probably an understatement.
"The boys have got to work a miracle to get that turned around for qualifying."
Verstappen later reported problems from his power unit similar to those that forced him into retirement at last year's Azerbaijan Grand Prix. The incidents occurred after Renault confirmed earlier this weekend that it had allowed all three of its teams to run more powerful engine modes.
Kevin Magnussen completed a long run on ultra-soft tyres at the start of the session before a late low-fuel effort on the softest compound saw him rocket up to sixth in the final standings. The Haas was ahead of the two Force Indias, which showed improved pace to finish ahead of the Renaults and Sergey Sirotkin's Williams, which crept up to tenth place in the tricky conditions.
The two McLarens of Fernando Alonso and Stoffel Vandoorne were outside the top ten in 12th and 13th, ahead of Brendon Hartley's Toro Rosso and Ricciardo's Red Bull, which did not set a quick lap before suffering its Renault turbo failure. Pierre Gasly was 16th fastest in the second Toro Rosso ahead of Lance Stroll's Williams and the two Saubers of Charles Leclerc and Marcus Ericsson.
Romain Grosjean failed to set a quick time in the Haas after his rear brakes caught fire midway through the session, limiting him six laps.
Formula 1 Heineken Chinese Grand Prix U.S. coverage presented by Mothers Polish (All times Eastern)
Qualifying - Saturday, April 14 1:55 AM - ESPN2
On the Grid - Sunday, April 15 - 1:30AM - ESPN2
Race - Sunday, April 15 - 2:05AM - ESPN2
Encore - Sunday April 15 - 1:00PM - ESPNEWS
Encore - Sunday, April 15 - 09:00PM - ESPN2