Brighton have completed the signing of Alexis Mac Allister from Argentinos Juniors, with the 20-year-old signing a four-and-a-half-year contract at the Amex Stadium.
Mac Allister will be loaned back to his former side until the end of the season, before Brighton decide whether to integrate him into the first team next season.
"Alexis is an exciting young player that we have brought in for the future, and he has already made a big impact playing in Argentina," Brighton manager Chris Hughton told the club's official website.
"It is in the best interests of all three parties to allow him to return to Juniors, as he will be able to continue playing regular first-team football in a very competitive league.
"We will keep a close eye on his development over the coming months, and it is a pleasure to welcome him to the football club."
Mac Allister told the club website: "The main reason I signed was because they came to Argentina looking for me, and they seemed very convinced about me.
"They made a big effort, told me about their project and their ideas to keep growing in this league, and I liked their ideas. I liked what they said."
Mac Allister came through the academy at Argentinos Juniors, making his senior debut for the Buenos Aires outfit in October 2016 at the age of 17.
The club secured promotion to Argentina's top flight at the end of that season and Mac Allister has gone on to make 58 appearances in total, scoring eight goals, including three in nine games so far this season.
Alexis' father, Carlos Mac Allister, was also a professional footballer, spending most of his career with Argentinos Juniors and Boca Juniors, and winning three caps for Argentina. His other sons, Francis and Kevin, are also on the books at Argentinos Juniors.