Reigning Formula One champion Lewis Hamilton admits he's never experienced a sand storm like the one that dramatically engulfed Bahrain for pre-season testing.
The seven-time world champion Hamilton took over from teammate Valtteri Bottas in what proved to be a frustrating testing for Mercedes in the Gulf state.
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Max Verstappen set the quickest pace for Red Bull as Hamilton and Formula One champions Mercedes endured a surprisingly difficult first day of testing.
Bottas was able to do only six laps in the first session due to a gearbox problem, with the wind and sand whipping up after lunch.
Hamilton managed 42 laps but was 2.2 seconds off the pace as the chaotic conditions proved more than a handful.
The combined tally of laps by the Mercedes pair was the lowest of all teams and Hamilton seemed to be struggling for grip on the sandy asphalt, while also having to deal with a wobbly wing mirror and complaining about the pedals.
“I’ve never seen a sandstorm come through here before in all the years that I’ve driven at this circuit,” Hamilton said.
“The sand was moving like rain would move. Having sand on the tyres isn’t good for their longevity and getting consistency on long runs is difficult.
“We only have a day and a half in the car before the first race. I’d like to think my nine years’ experience with this team will help me get the best out of it.”
Mercedes team boss Toto Wolff said the gearbox issue that thwarted Bottas "came out of nowhere".
"It wasn't a good start," Wolff said.
"If we have a smoother ride from here onwards then I think we can recover, if we have more stumbling blocks then with three days there's not a lot we can do."
Daniel Ricciardo had a much better time of things in his new McLaren after making a strong and smooth start to pre-season testing, despite the conditions.
The Australian was the fastest before lunch on the opening day on Friday before handing over to teammate Lando Norris, who ended up second overall to Red Bull's Verstappen on the combined timesheet.
"It was really good. It was a nice first half of the day. Everything went pretty smooth," Ricciardo, who has moved from Renault (now Alpine), told reporters.
"It's nice to see your name up the top but really the testing, especially day one, is just about reliability and making sure everything runs and it was a good morning. The team's happy.
"It was just a good feeling being back on track."
McLaren, third overall last year, have switched from Renault power to Mercedes this season and Ricciardo said there was no real benchmark to compare to at present.
Team principal Andreas Seidl said the programme had been completed as planned.
"For us in particular it's very important only having three test days and switching to the Mercedes power unit, it's very important to have smooth running," he added.
The Sakhir circuit is hosting three days of testing, half the amount the 10 teams had available last year at Barcelona's Circuit de Catalunya, before the opening race in the Gulf kingdom on March 28.
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