The South African has been experiencing problems on the greens but thinks he may finally have found a solution.
"The guys are giving me a lot of stick about it," he said. "But you know, these are legal tools. I want to give it a go.
"All the guys come up and said ‘Oh, you're not going to use that, you're not going to need that'. So they give me a lot of stick, but it's fine. I'll give it a go, and you know, we'll see. It's a bit of a new process but I'm working on it.
"For a while now, the normal swing, you're on plane, or you're not on plane. My putting, basically, my path became very awkward. I became too squared back and I cut through the ball a bit. You don't put a good roll on it and from short distances, I was becoming really not good. I started practising with a belly a little bit, and when you stick it in your belly, you know, it stays on plane.
"And that's basically what prompted me to use the belly. It feels very awkward to use it in a tournament to be honest, because I've always putted with a normal putter."
This is Els' third consecutive appearance in the event - and he has finished in the top-ten on both his previous visits.
But there is stiff competition this week from, amongst other, World Number One Lee Westwood, American Ryder Cup star Dustin Johnson and home favourites Y E Yang and Noh Seung-yul.
And 19 year old Noh is another player whose game is undergoing some changes.
“Two months ago I got a new coach, and we started making tweaks to my swing from address to finish,” he said.
“I was making a lot of effort, but as a result of this, I got a finger injury. So for a month, I wasn't able to practise, and I wasn't used to or haven't been adopted to the new swing.
“I have been practising for the two weeks. However, there have been mistakes and my shot was somewhat unstable. But through continuous practise, I feel that my swing is becoming a little bit more stable.”