Owen challenged for the British bantamweight title in his tenth professional fight in 1977. He defeated champion Paddy Maguire in the eleventh round to win the title, becoming the first Welshman in more than 60 years to hold the belt. Owen recorded five further victories, including a defence of his British title against Wayne Evans, before meeting Paul Ferreri for the Commonwealth bantamweight title. He defeated the experienced Australian on points to claim the Commonwealth title and challenged Juan Francisco Rodríguez for the European title four months later. The fight in Almería, Spain, was shrouded in controversy and Owen suffered his first defeat in a highly contentious decision.