West Ham manager David Moyes has boosted his defensive options with the signing of Danish centre-back Frederik Alves.
The 21-year-old has joined the Hammers from Silkeborg for an undisclosed fee and will link up with his new team on January 2.
A Denmark Under-21 international, the defender has been a regular for his club in the last two seasons and is relishing his move to the Premier League.
"I'm feeling very excited and I can't wait to get started," Alves told the Hammers' website.
"I was very excited to hear that a big team from the Premier League was interested and I'm very glad to be getting an opportunity at this club.
"My plan is to join up and train with the squad in January and, from there, to work hard so that I can play with the first team.
"I have great respect for the senior defenders here and I am the young one, so I am going to learn as much as I can from them because they are more experienced and know how the Premier League works. I am here to learn."
Alves, who has a Brazilian mother and Danish father, earned his chance at Silkeborg after two years in the Coritiba youth team.
He added: "I started playing football in Denmark, then we used to go to Brazil on vacation once or twice every year, so to keep fit I played football with my cousins and friends at their team.
"An agent saw me, liked me and spoke with mother and agreed for me to go on trial with Coritiba. I passed the trial and it went well, so I played over there for two years before I came back to Denmark in the summer of 2017 and joined Silkeborg."