The forward, handed the captain's armband by Wenger, had endured a year on the sidelines following a broken leg and fractured ankle - but showed he was back to his clinical best with a superb left-foot volley at the start of the second half.
Wenger feels the 26-year-old, who had marked his return to competitive action with a brace in the last round against Cardiff, has come back mentally stronger from his experience.
"It looked like a bit of a 'beach' goal - and he meant it, he sliced the ball," said the Arsenal manager.
"Eduardo is a surprising finisher and an intelligent player. He has short back lift and understands what to do very quickly.
"Goalscorers are moving in the box when everyone else is standing still, he has that.
"I have never seen him do that before, his goal was instinct and shows you that finishing is all about what you do in a fraction of a second."
Wenger added: "I did not expect him to come back like that, and it is a tribute to his personality. He has never complained and that is a big example in our world."