Halla began his career at SK Sturm Graz as a youth player, but played for city rivals Grazer AK from 1951 to 1953 as a right midfielder. 1953 he went to Vienna to play for SK Rapid Wien. For Rapid he played 289 matches and scored 39 goals. In the 1964-65 season he was team captain. [1] He played 346 matches for them until 1965. The last two seasons he played for SC helfort Wien.
On 23 November 1952 he debuted for the national team in a match against Portugal (1-1). His last match was on 13 June 1965 versus Hungary. [2] he played 34 international matches and scored two goals.