"We know the parts have worked, and we obviously would have liked them to have been a game-changer. It doesn't look at this stage like that, but then again we are yet to confirm them in real race conditions.
"It will be interesting and we are excited about seeing where the car will be in practice, and especially in the race.
"The team has a lot of experience. We know coming here what this track is about, the tyres and so on. We will see and get the final confirmation this week."
The concern for Ferrari is that it cannot consider itself a front-runner this season, and that is has slipped towards the midfield in a battle with Racing Point, McLaren and Renault.
"Realistically we are struggling with the performance at the moment," assessed Leclerc. "I think we can't consider us fighting for podiums at the moment, but we are trying to change that and to work hard as hard as possible to change this."
In contrast, Vettel attempted to offer a more optimistic view for the weekend at the Hunagroring.
"I think you can make the difference on this track," said Vettel. "We did improve our car, we know it has more downforce than the previous one.
"It's obviously not perfect and not great yet in terms of fighting for top positions, as Charles mentioned, but I hope this weekend is a bit better for us."
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