Fulham sign defender Alfie Mawson from relegated Swansea City

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Fulham continued their big-spending summer by securing the transfer of defender Alfie Mawson from Swansea City on Thursday.

Mawson will leave the relegated Swans to stay in the Premier League after signing a four-year deal with Fulham, who reportedly paid an initial £15 million with a further £5m in potential add-ons for the 24-year-old.

The centre-back was named Swansea's young player of the year in his first season in the top flight a year ago and was called up to the England squad in March, though he did not earn his first cap.

"I'm really happy to get this over the line and join Fulham," said Mawson, who grew up less than 15 miles from Craven Cottage and rose through the ranks of Fulham's local rivals Brentford.

"I'm excited by the project going on here and the football being played last season was lovely on the eye but also effective and I can't wait to be a part of it and get going.

"I'm excited to be a part of this great club moving forward and to help achieve success in the Premier League."

Mawson played in 38 Premier League goals last season, scoring twice -- including a winner against Liverpool -- before having knee surgery in May.

Newly promoted Fulham have had an active summer, signing Andre Schurrle, Jean Michael Seri, Maxime Le Marchand and goalkeeper Fabri, while also locking up striker Aleksandar Mitrovic to a permanent deal after his six-month loan from Newcastle.