Brighton have signed defender Eiran Cashin from Championship side Derby.

The 23-year-old centre-back has joined the Seagulls on a contract until June 2030, with sources saying Brighton have paid a fee of £9m.

Cashin has been a long-term target for Brighton and he was close to joining the Premier League club in the summer.

The Republic of Ireland Under-21 international was born in Mansfield and came through Derby’s academy.

Cashin made his first-team debut in 2021 and has already made 144 appearances for the Rams.

“He’s gained a lot of experience in the Championship, has a good profile and as a left-sided defender he will give us another strong defensive option,” said Brighton’s head coach Fabian Hurzeler.

Cashin made 44 appearances last season as he helped Derby win promotion back from League One back to England’s second tier.