Martinez reckons his newest star – who bagged 15 goals in La Liga last term for unfashionable Levante – will become a big hit in the Premier League.
“Arouna’s was as difficult an opportunity as you’re going to find,” Martinez told the Wigan Evening Post.
“He had so much time to think about what he was going to do in a one-against-one situation, away from home in a full stadium.
“But he showed how clinical and composed he is to kill the game.
“On top of that, his work-rate was exceptional, he held the ball up well, and in many ways it was the perfect debut.”