Charles Leclerc has warned Ferrari must work on its tyre management ahead of Sunday's Spanish Grand Prix.
The championship leader topped both practice sessions on Friday but as in Miami, Ferrari's vice was tyre management in the searing Spanish heat as Leclerc complained of his medium rubber "falling to pieces" after only eight laps.
Despite the promising qualifying pace, the Monégasque is concerned by the high degradation.
"Our qualifying runs don’t look bad, but we have some work to do, in particular on our race pace and on tyre management," said Leclerc.
"The stints we did on the soft compound felt better than those on the mediums.
"We will analyse our latest data to find where we can improve on this track, as the conditions are very different to the last time we were here during winter testing."
Sainz hoping to ride home crowd vibes
Leclerc's team-mate Carlos Sainz finished the day fourth fastest, with the Ferrari's split by Mercedes duo George Russell and Lewis Hamilton.
The Spaniard suffered from the same tyre issues as his Scuderia stablemate but is hoping to ride the wave of support from the sell-out home crowd throughout the rest of the weekend.
"A bit of a tricky FP2 compared to a positive FP1, as we struggled a bit with tyres and balance after the changes we made," explained Sainz.
"We need to look at it and find the correct adjustments for tomorrow, but we’ve got plenty of data and I’m sure we’ll find a more comfortable set-up.
"It seems like there is a lot of degradation with the heat, which could be crucial for the race, so we’ll also keep an eye on that.
"I’m very impressed with the number of fans in the grandstands today. It’s fantastic to see all these people supporting us and their good vibes are a huge motivation."