While at Brøndby, he secured a place in the national team starting line-up and played 38 matches in a row from October 1992 to August 1996.

Rieper won the 1994 Danish Cup trophy with Brøndby before moving abroad in December that year to play for English Premiership club West Ham United, signing initially on loan before a £1 million fee at the end of the season made the transfer permanent.

[7] Rieper played 61 matches and scored two goals for the Denmark national team, first as the defensive partner of Lars Olsen and most prominently as part of a defending duo with Jes Høgh in the UEFA Euro 1996 and 1998 FIFA World Cup tournaments.

Through his connections to Celtic, he brought over many reserve team players to AGF, including future Republic of Ireland footballer Liam Miller.

owns and runs a hotel in the town of Aarhus, is a member of the board of directors at AGF and is the owner of women's online fashion store BA10.dk.