Ajax coach Erik ten Hag says failing to register Sebastien Haller for the Europa League "is no laughing matter".

The former West Ham striker's name was missing when UEFA released Ajax's squad ahead of their tie with Lille, with it later being confirmed it was an oversight on the Dutch club's behalf.

Ten Hag conceded: "This is of course no laughing matter.

“It's incredibly annoying, for the club and the player in question. Haller showed in January just how valuable he can be. What was the problem? It has to do with computers and turning a check mark off or on. Of course we will do all we can to get him to play, but this is of course not a futility.

"It has very big consequences. So then it thunders internally. Ultimately, Marc Overmars and I are responsible for it."