Although Mercedes are starting 1-2 on the Bahrain Grand Prix grid, Lewis Hamilton is wary of the challenge that Ferrari will pose in race-trim.
While Ferrari set the pace in Friday's practices at the Sakhir circuit, Mercedes came to the fore in Saturday's qualifying.
Valtteri Bottas claimed his maiden pole position with Hamilton grabbing second place on the grid.
Ferrari's Sebastian Vettel was third, almost half a second down.
Hamilton, though, reckons Ferrari aren't done and expects the Scuderia to fight back on Sunday evening.
He said: "I think the Ferraris are very quick on race-trim so hopefully it will be very close.
"Today we obviously had a bit of a margin to the Ferraris, but generally in race-trim they seem a bit quicker.
"It will definitely be a close battle.
"I don't know how their long runs run but I think they were good.
"It will be interesting to see temperatures and we will hopefully have a great battle."
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