|Full name||Roque Germán Olsen Fontana|
|Date of birth||9 September 1925|
|Place of birth||Sauce de Luna, Argentina|
|Date of death||15 June 1992(aged 66)|
|Place of death||Sevilla, Spain|
|1963–1964||Deportivo La Coruña|
|1970||Deportivo La Coruña|
|* Senior club appearances and goals counted for the domestic league only|
Olsen started his playing career in the local leagues of Parana, Entre Ríos. In 1949 he was signed by Tigre, the following year he joined champions Racing Club de Avellaneda. After only 15 games for Racing he joined Real Madrid where he went on to become one of the club's most important goalscorers. He played out his career with Córdoba CF in the late 1950s.
Olsen started his managerial career with Córdoba CF leading them to promotion to La Liga in 1962. He then managed Deportivo La Coruña, Real Zaragoza and FC Barcelona. He also managed Elche CF, Sevilla FC and Celta Vigo. His last managerial position before his death in 1992 was as manager of UD Las Palmas.