Former Manchester City reserve keeper Pantilimon was signed by the Stadium of Light club in June and has signalled his intent to fight for the number one jersey.
However, Mannone is relishing the competition and hopes to prove to head coach Gus Poyet that he is the best man for the job.
"There is nothing new about having competition - it has happened at every club I have been at," he is quoted as saying by the Northern Echo. "This is football and it is normal.
"Maybe sometimes for the people outside the club it is strange, but it is normal for us as players.
"I just need to prove that I am the best, and I need to give every reason to the gaffer to keep picking me."
Sunderland begin their Premier League campaign at West Brom on Saturday.
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