Charles Leclerc and Sebastian Vettel put Ferrari at the top the timesheet on the opening day of running in Baku but both drivers are expecting a fierce battle with Mercedes in qualifying.
Leclerc edged his Scuderia team mate in FP2, with reigning world champion Lewis Hamilton concluding the day's single session seven tenths down on the Monegasque.
The 21-year-old looked fired up on Friday and determined to lead the way in Azerbaijan, but Leclerc expected Mercedes' chargers to unleash the full might of their W10 on Saturday afternoon.
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"I’m quite confident with the car, quite confident with the track, so overall it’s a good day," Leclerc said.
"But looking at their pace in the race run, I expect quite a lot more from them tomorrow in qualifying. I’m absolutely sure there is more to come from Mercedes.
"They were very quick on the long runs, so there is no reason they are slow on the short runs.
"I am sure tomorrow when they put everything together, it’s going to be very tight."
©Ferrari
Vettel agreed that beating the Silver Arrows squad remained Ferrari's biggest challenge.
"Mercedes will be the ones to beat. Red Bull also looked fast at times so I think it will be close tomorrow," said the German.
"Here, to be honest, it’s mostly about having the confidence in the car with so many big stops after high-speed braking and very little reference. It’s easy to do mistakes over the bumps and go straight.
"Overall I think it will be decisive tomorrow to have a good feel with the car and that’s what we are working towards."
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