Nasri hit the winner on his Premiership debut against West Brom on Saturday and Wenger said: "He has a bit of [Robert] Pires in him maybe, because he looks to be able to change direction very easily.
"Nasri had a bad season last year because he had meningitis, he was in hospital for two weeks, then did not recover properly for three months.
"They rushed him back to play and of course he was not at the expected level.
"However, the year before everybody wanted him, sometimes you have to be brave enough when everybody says he is not good."
Wenger added: "I saw him start his first game and he gave me an impression that you keep with you, and when you see things you have to go with your beliefs."