Charlton have signed Denmark Under-21 winger Martin Christensen on a four-year deal for an initial £250,000.
"He's a great prospect. We think highly of him," said Addicks boss Alan Pardew, who could pay an additional £100,000.
"It's going to be a big step up for him to this level but he's of a good age and we feel he'll progress quickly."
The 19-year-old joins on a pre-contract basis from Herfolge Boldklub and Charlton have also agreed a three-year collaboration with the Danish side.
Herfolge, who won the Danish Superliga title as recently as 2000, have established a fine reputation for youth products.
When Christensen links up with his new team-mates in the summer he could become the third Dane in the Charlton squad, with senior international Dennis Rommedahl and goalkeeper Mads Nielsen presently at the club.