The Netherlands international arrives in the Italian capital on a five-year contract, with the initial cost of the transfer standing at €14 million, which could rise to €19 million with bonuses.

Right-back Karsdorp is a product of the Feyenoord academy and helped the club to the Eredivisie title last season.

"Coming to AS Roma is a great step forward for me," Karsdorp said. "I come here with a great desire and enthusiasm to play and to realise my dreams.

"I know I still have a lot of room to improve and I hope to do that here."

Roma sporting director Monchi said: "Despite his young age, Rick has already shown he possesses great talent.

"We are delighted to be able to sign him, and are certain that his attributes will fit in well with the way coach Eusebio Di Francesco wants to play."

Karsdorp made 101 senior appearances for Feyenoord during his time at the club.