The Italian goalkeeper swapped the Gunners for the Black Cats last summer after failing to dislodge Wojciech Szczesny and Lukasz Fabianski in the pecking order at Emirates Stadium.
I’m very proud of what he’s doing
Mannone has managed to establish himself as a first-team regular under Gus Poyet following the Uruguayan’s appointment as Paolo Di Canio’s successor at the Stadium of Light.
The 25-year-old has been one of Sunderland’s standout performers in their bid to avoid relegation, keeping three clean sheets in his last three Premier League games.
And Wenger admitted it is a satisfying feeling to see Mannone fuffil his talent at Sunderland.
“That’s the problem he faced here,” Wenger told Arsenal’s website.
“I sold him because of that. At some stage you cannot block the career of the player.
“I’m very proud of what he’s doing because I kept him here when he had a trial at the age of 16 because I saw something in him. That’s coming out now which is of course very satisfying.
“He is a football man, he loves the game and I was always convinced that he would be a great goalkeeper.”
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