Nordahl made his debut in the Allsvenskan in 1964 for Degerfors IF when he was 17 years old. A year later, he moved to Örebro SK and became a key player there. He played 77 matches for the Swedish side and scored 41 goals. 1968 he moved to the Italian club Juventus, who had finished third in serie A the 1967–68 season. However, shortly after Nordahl signed the contract, the Serie A issued a ban which stopped all clubs from bringing in foreign players. Nordahl was contracted with Juventus but couldn't play because of this ban. This forced Juventus to loan him out to Belgian side R.S.C. Anderlecht. Nordahl stayed in Anderlecht for three years, until 1971; after those three years, his contract with Juventus ended, but the ban still had not been lifted. Nordahl left the club without playing a match for them and went to his old club Örebro. He played there for 7 years between 1971 and 1978, making 175 appearances and scoring 65 goals, resulting in a total of 252 appearances and 106 goals for the club. In 1979 (the season began 1980) he went to another Swedish club, BK Forward, and played 45 matches and scored 21 goals. In 1980, an injury forced Nordahl to quit playing football and the age of 34.