Ferrari's Charles Leclerc was impressed by his one-lap pace in Friday's practice for the Portuguese Grand Prix but admitted to being in the dark still regarding his car's speed in race trim.
Leclerc was fourth in both practice sessions, confirming the Italian outfit's progress of late on the back of changes to its SF1000 aero package.
But a lack of long runs on Friday incited the Monegasque to remain cautious going forward.
"It looked quite good today," said Leclerc. "Let’s wait and see, we haven’t done much high fuel running with normal tyres, we did some with the prototype tyres, and that was our weakness in the last race.
"It will be a bit of a surprise on Sunday when we’ll see where we’ll be, but on the qualifying pace looks quite promising
"The car is a little bit difficult to drive at the moment but it looks like the same for everyone in the paddock.
"I guess it will be up to the guy who does best lap without making any mistakes in qualifying and we’ll try to extract the maximum out of the car."
Sebastian Vettel clocked in sixth in FP2, a little over three tenths behind his teammate. But the German driver also adopted a cautious stance.
"In the end it was one lap time and not everybody got their lap in because we saw today that you needed more running. One, probably for the drivers to get in the rhythm, second, mostly for the tyres," he said.
"I think we’ll see the true picture tomorrow but it felt quite OK. I mean, the car is a bit all over the place also due to the elevation changes, but I think that’s the same for everyone."
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