The Italian squad had impressed in Friday practice but, in its preparations for qualifying, the team appeared to lack pace at the start of the lap relative to the cars ahead of it in the battle for pole position.
GPS traces show that his Ferrari was between 3-4kph slower on the straights compared to the two McLarens, and even more in arrears compared to polesitter Max Verstappen - thanks to the tow the Red Bull driver picked up from Nico Hulkenberg.
Leclerc felt that Ferrari's ultimate grid positions, which became third and fourth when Oscar Piastri was given a three-place grid drop for impeding Kevin Magnussen in FP1, cost a shot at anything more than third.
"Looking back at yesterday, reanalysing qualifying. I think we basically lost everything at the launch [of the lap] for some reason," he said.
"We had a slightly different power strategy compared to McLaren and Red Bull, and we lost everything on the run down to Turn 2 - Max, on top of that, had the slipstream.
"This is something we'll have to look into because, especially on a track like this, track position is absolutely everything.
"When you only have a tenth in between Red Bull, McLaren, and ourselves, we need to do everything perfect and the third place today cost us maybe a better result in the race."
Explaining his first impressions of Ferrari's comprehensive suite of upgrades for the Imola race, Leclerc contended that it was difficult to judge them given the demands of the Imola circuit.
But he was confident that the team had attained its objectives with the new bodywork, floor, and wings that it had installed for its home race.
"I think first of all, it's not the best track to judge upgrades, mostly because kerb-riding is such a thing here that if you have a good car on kerbs, then that could hide a bit more what is the real order," the Monegasque said.
"The good thing is that everything we expected from those upgrades, we had it in terms of data. It did exactly what it was supposed to do, which is always a good thing."
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