Mandić started his solo career in 1978 with the single "Ljuljaj me nežno" ("Rock Me Gently"). He composed the song, with Marina Tucaković's lyrics, for the singer Slađana Milošević, since the song was composed after her major hit song "Sexy dama", 1978. as a continuation of her musical style. Slađana Milošević was the one who persuaded her school mate Oliver to start his singing career and sing "Ljuljaj me nežno" by himself. Oliver publicly thanked her for that in several interviews and occasions. Milošević herself did not want to continue down that avenue and after her refusal the song was offered to a singer Maja Odžaklievska, however, since she failed to show up in Split studio Tetrapak for a booked recording session, Mandić agreed to accept another suggestion made by producer Enco Lesić to record it himself. The material was released the same year as a two-side single "Ljuljaj me nežno" / "Šuma" by PGP-RTB, garnering positive reactions both commercially and critically. A year later, Mandić recorded another successful single, featuring the songs "Sutra imam prazan stan" ("Tomorrow I'll Have an Empty Flat") and the ballad "Osloni se na mene" ("Lean on Me").