F1 promise George Russell, 22, was the fastest in the Sakharir GP’s first free practice on Friday.
Russell, who drove a Mercedes car for the first time, was immediately faster than his teammate Valtteri Bottas, who had enough time in fourth.
Bottas was 0.322 seconds behind Russell.
At the end of the rehearsals, he lamented on team radio that his left front wheel was constantly locked.
Between the Mersuk drivers were Red Bull’s Max Verstappen and Alexander Albon.
Williams driver Russell will drive this weekend on Mercedes as British champion Lewis Hamilton is in the crown of the crown.
Russell from England is a Mercedes protector who has gone through the stable’s junior program.
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Alfa Romeo's Kimi Raikkonen was 14th in practice.
Two other luck drivers were also seen in Russell's shadow.
Romain Grosjean, injured last Sunday, was replaced by Pietro Fittipaldi, who finished 19th in Haasilla.
Jack Aitken, who succeeded Russell Williams, was 20th or last.
This weekend, the Sakhiri track will be run on the so-called outdoor track, which is fast and short.
The rounds last well under a minute.
Russell’s fastest time was 54,546 seconds.
Last Sunday, Hamilton won the Bahrain GP on Sakhir’s “basic track”.
Hamilton has already secured this season’s world championship.
Friday’s second rehearsals begin at 7:30 p.m.