Red Bull's Max Verstappen completed a clean sweep by topping the times in a rain-curtailed third practice on Saturday for the Turkish Grand Prix. On a miserable cold and wet morning at the ultra-slippery resurfaced Istanbul Park Circuit, back in use for a Grand Prix for the first time since 2011, the Dutchman clocked a best lap in one minute and 48.485 on intermediate tyres before the rain intensified.
It was enough for him to be a second faster than Ferrari's Charles Leclerc with his Red Bull team-mate Alex Albon third, 1.6 off the pace. Esteban Ocon of Renault was fourth, but a further four seconds adrift.
Lewis Hamilton, seeking to seal his record-equalling seventh drivers' world title, ventured out for a couple of exploratory laps in his Mercedes, but without clocking a time.
"No grip out here at all, it's shocking," he said.
"It's like ice driving, which I did in the winter," said Russian Daniil Kvyat after slithering and drifting across the glistening surface in his Alpha Tauri.
He was one of the few drivers laughing in conditions that may delay or even postpone qualifying later Saturday.
Lando Norris was fifth for McLaren ahead of four-time champion Sebastian Vettel in the second Ferrari and Racing Point's Sergio Perez, who on Friday compared it to like "driving in your kitchen".
Hamilton's Mercedes team-mate Valtteri Bottas, the only man who can stop the Englishman taking the title again, was eighth ahead of Kevin Magnussen of Haas and Lance Stroll in the second Racing Point.
After Friday's 'ice rink' conditions, the drivers had colder weather and rain to add to their challenge as third practice began. A message from Race Control confirmed it was official: 'Low Grip Conditions', it stated.
Out on track, the spinning began almost immediately. Led by Perez, Ocon, aided by a nudge from Perez and Norris all following his example.
Leclerc was quickest in the early stages before Verstappen went top on intermediate tyres as the rain intensified, most teams opting to switch to full wets.
By the half-hour mark, the heavy rain had persuaded everyone to retreat to the pits.
Hamilton had ventured out only for an inspection lap and no-one, other than Vettel on 14, had done more than a bare handful of laps.
In the Red Bull garage, Verstappen chatted with reserve driver Juri Vips. The spin count had by then grown to include Kvyat, Sainz and Leclerc, who did well to keep his Ferrari out of the barriers.
With 20 minutes remaining, there was little prospect of further action - everyone being aware that one error in the rain could ruin their prospects for qualifying and use up sets of the limited supply of full-wet tyres.