Brentford manager Thomas Frank has called Chelsea insane for spending €100million on the transfer of Mykhailo Mudryk from Shakhtar Donetsk.

The Blues confirmed the arrival of the 22-year-old Ukraine international winger on Sunday following a battle with fellow Premier League side Arsenal for his signature.

Chelsea will pay Shakhtar Donetsk a total of €100m (£88.5m) for Mudryk with €70m (£62m) up front and €30m (£26.5m) in add-ons.

“There’s a lot of money around in the football world,” Brentford boss Frank said when quizzed about Mudryk’s move to Chelsea. “Especially in the Premier League.

“Looking from the outside, I think Mudryk is a really good player but €100m is a lot for a player that is [only] showing great signs of potential.

“He probably needs to do a bit more, but maybe that’s just the price tags these days. I think it is insane.

“They bought him… then they bought… no… oh, there is rumours about the PSV guy [Noni Madueke] as well. I think they have enough wingers, that is their issue!

“Sometimes in a bidding war, the price will go up and then in some cases you are going to pay too much.

“It looks like a very, very expensive player. With his CV, it is a lot of money. But maybe it will be worth it in two years time.”