Napoli striker Arkadiusz Milik admits their first-half set up defeat to Champions League rivals Shakhtar Donetsk.

Shakhtar defeated the Italians 2-1 in Ukraine.

“It's difficult to say why this happened, it's the second or even third game when we don't start really well and have to change, because the first half was really, really bad," Milik told Mediaset Premium.

“We didn't have the ball the way we want to, didn't create the chances we wanted to. In the last 20-25 minutes we started to create chances and play the kind of football we want, but it was too late to win the game."

It is also perhaps no coincidence that Napoli's performance was transformed when Mertens came off the bench.

“Mertens played really, really well, gave us a lot of energy, quality and created a lot of chances. The penalty was because of him. He is a big player and what more can I say? The worst thing is we lost and now we have to look forward and focus on the League."