At age 17, Jenő Károly played both in the Hungarian first division at MTK and on the national team. He won two league titles (1904, 1907-08), as well as leading the league in scoring in 1903 with 15 goals, and in 1905 with 13 goals. In the 1909-10 league year, he was chosen the player of the year. Between 1910-19 Károly played for the BAK team. His best result with BAK was a third place in the 1911-12 season. Between 1903-18, he played in the national team 25 times and scored 10 goals, playing at the 1912 Stockholm Olympics. Between 1920-26 Károly worked in Italy as a coach, before dying at the age of 40. As Juventus coach, he sustained a heart attack during the title match, but Juventus won the match and the championship.