Charles Leclerc says his efforts in Sunday's Portuguese GP were thwarted by graining on the medium tyre, a hindrance that nevertheless allowed the Ferrari driver to score a P6 finish.
Leclerc was at a loss to understand why Pirelli's medium compound was such a poor fit for the Scuderia's cars as teammate Carlos Sainz, who finished just outside the points after a promising performance in qualifying, was also hindered by the graining issue.
"I think we took a great decision to go on the hard tyres, but the mediums for us – only for us – we struggled massively, whether it was Carlos or myself," said the Monegasque.
"Me in the first stint and Carlos in the second stint, we had a lot of graining on the medium tyres straight away and struggled a lot on that compound.
"I don’t have any explanations. On paper it looked like a very good choice. But we struggled a lot."
Leclerc said the unsatisfactory result capped off a weekend in which he believes he should have done a better job overall.
"If I look at the whole weekend, I haven’t done a great job as a driver," he said.
"Whether it was in free practice, qualifying I didn’t extract the maximum out of the car because I was very inconsistent; today I’ve done a good job and I think from eighth there wasn’t much better we could do.
"But looking at the whole weekend, I could have done a much better job," he added.
"With the wind it’s been very tricky all weekend, especially with those cars, the braking points are changing and I never really found any good references.
"In the race I found my rhythm, but I’m looking forward to getting back to ‘normal’ conditions and a ‘normal’ track to be better."
Although disappointed with his weekend, Leclerc confirmed once again Ferrari's clear progress.
"It’s encouraging for the whole team," he said. "We were struggling a lot last year, we did a step forward this year and we need to keep in mind also that Portimao is quite a strange track.
"Last year we were a lot quicker [there] than in other races and we didn’t know why. So let’s wait for Barcelona and see where we start again."