Arsenal boss Mikel Arteta has explained the surprise selection of Ainsley Maitland-Niles for their FA Cup semifinal win over Manchester City.

Arteta sprang a surprise by selecting Maitland-Niles at left wing-back - but the decision paid dividends.

"Absolutely, [he was magnificent]," said the head coach. "And I was sure about that with the way he's training, the way he's changed his mentality and his mindset.

"He has everything, he has great qualities, I believe in him. I had to give him opportunities and today he took it with both arms. He had a really good performance.

"It feels incredible. I'm so proud today. To bring the club back into a final... we'll see who we will face but now we make sure we finish the league the way we should."