Hrubesch played in small clubs until the age of 24 when he was signed by Rot-Weiss Essen. There, he played well enough that in 1978 Hamburger SV (HSV) bought him. At Hamburg he blossomed into one of the most productive forwards of the Bundesliga and was soon called up for the West German national team. Hrubesch formed an attacking partnership with fellow HSV player Manfred Kaltz, a right wingback whose crosses Hrubesch often headed in, or headed to teammates to provide them with scoring chances. Hrubesch won the West German championship three times with Hamburg, in 1979, 1982 and 1983; and his team finished second in the league standings twice, in 1980 and 1982. In all, he scored 96 goals in 159 matches for the club.