Retallick was cleared out in a ruck by Springboks opposite RG Snyman and landed awkwardly on his left shoulder. He was in visible pain as he walked off in the 61st minute of the 16-16 draw in Wellington.
Hansen did not give a timeline for his return to reporters on Sunday but sounded optimistic the former World Player of the Year would be fit to travel to Japan for the Sept. 20-Nov. 2 showpiece.
"Hopefully he will be available for the World Cup. He is one of our best players so that's good," the coach said.