Ocon and Leclerc were on the grid against each other in 2018, with the Frenchman racing for Force India (now SportPesa Racing Point) and the Monegasque for Sauber (now Alfa Romeo Racing).
But while the 22-year old was on the side-lines for 2019 as Mercedes reserve driver he watched on as Leclerc took two wins and seven pole positions throughout the season for the Scuderia to finish ahead of Vettel in the championship.
“I said to everyone, including at Mercedes, that Charles was going to be at this level and beat Sebastian [Vettel] after a couple of races and no-one believed me at that time. Now they do!” he said to ESPN.
“I've been racing against Charles for a long time and he is one of the tough guys and I have been racing against him and Max and they were the two best.
“So I am not really surprised, but of course I hope we are going to be a long, long time in Formula One racing against each other for the title in the future.”
Ocon returns to the grid for 2020 with Renault alongside Daniel Ricciardo and believes he has the capability to race against Leclerc and Aston Martin Red Bull Racing’s Max Verstappen.
“Well, as a racing driver you have to believe you are better than them,” he added.
“But you are not allowed to show it or say anything!”
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