Australian heavyweight Justis Huni is aiming to climb further up the world boxing rankings when he defends his WBO Global heavyweight title against South Africa's Shaun Potgieter. Huni, 25, has a date with Potgieter, known as "God's Warrior", at the Gold Coast Convention Centre on January 8. The heavyweight showdown is on the card with Australian cruiserweight Jai Opetaia's IBF …