Wilshere drilled home from the edge of the area in the 86th minute after the Gunners had piled the pressure on Swansea following a goalless first half.
The 20-year-old midfielder has been one of the north London side’s standout performers this term since missing the whole of last season with knee and ankle problems.
And the Arsenal boss was thrilled with the England international’s impact at Emirates Stadium on Wednesday.
“Jack was outstanding tonight,” said Wenger. “I felt many players played well. As a team we played well and he was in a different position, he was high up and it suits him well.
“I have no experience of player being out for 17 months in my whole career, but honestly I always said that if we got Jack on 1 January, then we would have done well. But he is ahead of what I could imagine.”
“A complete midfielder can defend and attack and Jack can also dribble and give a final ball. So the closer players like him are to the goal the better it is for them.”
The replay victory sets up a fourth-round clash at Brighton and Hove Albion and Wenger was quick to play up the importance of the FA Cup as the Gunners look to end their lengthy trophy drought.
“I would not like to think the Premier League is less important [than the FA Cup] – we have to fight very hard to get back into a better position there,” he said.
“But we are in a position where you lose at home to Manchester City your confidence drops very quickly. So no matter what competition it was tonight, we just wanted to win the game.
“We go to Brighton now, and we will play with full power but there was more at stake tonight than just the FA Cup.
“[The priority] was to win again after losing such a big game on Sunday it was important to come back and win straight away.”
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