Born in Copenhagen, Karl Aage Præst attended the Royal Orphanage. The orphanage became the youth team of football clubØsterbros Boldklub in 1936, and Præst was among the first boys to join ØB. In his second year in the ØB youth team, Præst scored 57 goals in 16 games. He made his senior debut in 1940. At ØB, he played alongside later Danish international Helge Broneé. Præst was acknowledged as a world-class talent, with great balance and dribbling, and a great end-product of either precise crossing or a good shot on goal. Præst played around 250 games while at ØB. He became internationally known through international exhibition games for Danish representative teams Stævnet and Alliancen, and made his debut for the Denmark national football team in June 1945. In May 1947, he was selected for the Europe XI representative team, which lost 1-6 to the Great Britain national football team. Præst was a part of the Danish team at the 1948 Summer Olympics in London, where Præst played four games and scored two goals as Denmark won a bronze medal. After the Olympics, Præst signed a professional contract with Italian club Juventus F.C., and was thus banned from the amateur-only Danish national team. With Juventus, Præst won the 1949–50 and 1951–52 Serie A championships. Though considered fast in Denmark, Præst was not as fast as most Italian defenders, but succeeded through his dribbling skills. Præst played alongside Danes John Hansen and Karl Aage Hansen at Juventus, and his dribbling and crossing ability was a key in making John Hansen top goal-scorer of the 1951–52 season. Præst played 232 games and scored 51 goals for Juventus in the Serie A championship from 1949 to 1956. In 1956, Præst moved on to league rivals S.S. Lazio. He played seven games for the club, before ending his career in 1957. Upon his return to Denmark, Præst's status as ex-professional meant the Danish Football Association kept him banned from playing in the Danish leagues. Præst and John Hansen had both bought vacation homes in Liseleje, and Præst's summer residence "Juve" was soon the gathering place of the 1948 Olympics team. The team was reformed, amateurs and ex-professionals alike, and played a string of unofficial high-profile exhibition matches that drew many spectators. This provoked DBU to move on the issue of ex-professionals, and it was decided that following a quarantine of two years, ex-professionals were allowed to re-enter the Danish football league. At ØB's 75th anniversary in 1969, Præst and Flemming Nielsen arranged an old boys exhibition match between the 1948 Olympic team and Juventus FC, with the proceeds going to ØB. In November 2008, Præst was voted into the Danish Football Hall of Fame, for his achievements with Juventus FC and the Danish national team.
