Millwall have completed the signing of Derby winger Ryan Smith for an undisclosed fee.

The 20-year-old impressed during a loan spell with the Lions at the tail end of last season and has earned a permanent switch to the New Den.

He is Willie Donachie's fifth signing of the summer and will join new-boys Scott Barron, Gary Alexander, Andy Frampton and Danny Spiller for pre-season training.

Donachie told the club's official website: "He's an excellent acquisition for us.

"Ryan has great talent, speed and is an exciting player with real potential."