Cools joins Club Brugge
The Jupiler Pro League side reached an agreement with the Belgium U19 international last Friday.
The deal was finalised after he passed his medical on Monday.
"Dion is a player who fits our philosophy perfectly,” said general manager Vincent Mannaert of Cools, who helped OH Leuven achieve promotion to the Jupiler Pro League next season.
“We signed Dion as an option for the future, but perhaps he can surprise us sooner like [Club Brugge and Belgium right-back] Thomas Meunier did a few years ago.”
Cools, who can represent the Harimau Malaya as he has not played at full international level for Belgium, previously revealed to FourFourTwo Malaysia that he has not been approached by any Malaysian club so far.
Club Brugge finished top of the league table in the regular 2014-15 season but narrowly lost out on the league title to Gent in the championship playoff.