Kimi Raikkonen says the first test has shown him the Ferrari SF16-H has "a lot of potential".
Ferrari is targeting challenging Mercedes for the championship this season, with team principal Maurizio Arrivabene saying he wants to be in the fight until the end of the year.
Asked what is the main positive he will take away from the first test after setting the fastest time on Thursday, Raikkonen replied: "To get the first feeling of the car and I am sure that there is a lot of potential.
"It feels better than last year’s package, and that was the aim. It is very early days, and we have not done a lot of set-up work with it. For sure we can improve it, so we are just doing the normal work."
While Raikkonen admits Ferrari has lost a lot of time after he was limited to 80 laps on Friday, the Finn is not concerned by the mileage that Mercedes has managed.
"Why should I be worried? It is something that some other people do, and we do our own stuff. Obviously we would like to have done more laps; it was almost one day out of two (off the track).
"But it is a part of testing and we are getting ready to go racing, if there are some issues of some things to change or try, we will to it. It is up to us to make sure we are in the right position when we start racing."
REPORT: Raikkonen fastest as McLaren completes just three laps
Day four of the first test as it happened
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