The 24 year-old connected with a crushing uppercut to Haumono’s jaw, which didn’t really land flush, but was enough to drop his compatriot for the count.
Veteran Haumono, 40, crumpled to the canvas and Parker celebrated his 17th career stoppage to move on to a potential world title shot later this year.
Parker is mandatory challenger to UK powerhouse Anthony Joshua and could well be in the opposite corner when the world champion returns to action in London at the end of this year.
Joshua has so far KO’s all seventeen of his opponents inside seven rounds but is rumoured to be considering an American/Canadian opponent for his next defence.
Due to his lucrative deal with Showtime in the US, Parker may have to wait until the spring of 2017 to land his shot, all being dependent on when Joshua wants to make his Stateside debut.
If Joshua is pencilled in to cross the Atlantic early next year, Parker would then be drafted in this year in a bid to fulfil obligations to the IBF.
In the Horncastle Arena co-feature, heavyweight Izuagbe Ugonoh also recorded a fourth round finish against Argentinian Ricardo Ramirez to push his unbeaten run to 16-0.