Esterhuizen, who will become the 68th Springboks captain in their one-off test against Australia in Perth on Sunday, is one of several players in the squad who can play multiple positions, something Erasmus is trying to nurture ahead of their global title defence.
He will start at centre but could well move to the side of the scrum in the second half, though Erasmus has also revealed they have been trialing hooker Malcolm Marx as a flanker too ahead of the game and he could be unleashed in that position off the bench.
"I think I see the game differently now," Esterhuizen told reporters on Saturday. "I understand when the forwards might be getting tired, which is something you don't always appreciate as a back until you've done that work yourself.
"It helps me know what to look for. After a long passage of play or a big scrum, you understand exactly how the forwards are feeling and what the next call should be."
Esterhuizen will partner Canan Moodie in the centres, with Erasmus making 13 changes for the clash after a bruising recent 3-1 series win over New Zealand.
"I'm very excited to play with Canan again," Esterhuizen said. "We've always played well together, we have a good partnership and we know each other really well.
"We talk quite a bit, both on and off the field. Before games, we usually sit down and talk through different scenarios.
"He knows what I'm likely to do in certain situations, when to run off me and when to go for the ball. I think we're in each other's heads a little bit, which helps a lot."
Esterhuizen takes over the captaincy of the side from the rested Siya Kolisi and says he has learnt much from the double World Cup-winning skipper.
"Siya has been a tremendous leader for the Springboks, and I've obviously played alongside him at the Sharks as well," he said.
"One thing I've always noticed about him is how composed and calm he remains, no matter what the situation is. He also knows how to rely on the players around him.
"He knows when to step back and when to step up, and that is something I've taken from him."
