At the Hungarian Grand Prix, Leclerc led Vettel for the majority of the race, only for his disintegrating tyres to cost him pace, which allowed the German to overtake for the last podium place with a few laps remaining.
The Ferrari rookie admits he needs to identify the reason for Vettel performing better on longer stints.
“There’s definitely something that Seb is doing better than me in the long runs, when there’s degradation,” said Leclerc.
“I think I need to understand something on my side. I’ve been struggling more, and have more tyre degradation compared to Seb, and I believe it’s also coming from driving.
“Maybe I’m driving a bit too aggressively now in races, so I need to understand and analyse and try to improve for the next races.
“I’m pretty sure that Seb is doing something better than me there, so I need to understand and improve that.
“That’s a few races where I’m quite quick in qualifying, but towards the end of the race I seem to struggle a bit more.
“I need to understand what I can do with my driving style to help that, or with the car balance to have a little bit of a compromise between the two, because at the end it’s the race when you score points.”
After the opening 12 races of the 2019 Formula 1 season. Vettel leads Leclerc by 24 points, although neither driver has managed to pick up a GP victory as of yet.