The 23-year-old left-back will now join up with Dean Smith's squad ahead of their return to the Premier League.

His transfer fee could rise to a potential £17m with add ons.

Smith was pleased to capture the England under-21 international, who made 21 appearances for Saints last season.

Targett spent 15 years at Southampton, where he was a product of their thriving academy.

Smith said: "We're very pleased to have Matt join us.

"He's a player we have been looking at for a considerable amount of time.

"He fits our criteria of being a young player with experience of playing in the Premier League and having the potential to develop further.

"He will help make us a stronger defensive unit and we are all looking forward to working with him."

Targett said: "Dean is building something special here.

"The club has a massive fanbase and I'm looking forward to playing in front of them."

Southampton, meanwhile, have bought Birmingham City striker Che Adams for £15m.