Darren Clarke posted an opening round of 69 in testing conditions to lie two shots behind leader Raphael Jacquelin at the Volvo Golf Champions in Durban.
2011 Open champion Clarke has lost almost three stone in weight since October as he looks to reproduce the golf which brought him a first major title at Royal St George's.
The 45-year-old has failed to record a single top-10 finish on the European Tour in the last two seasons.
However the Dungannon native can take many positives from day one at the Durban Country Club, as he posted five birdies, including one at the last for a three-under-par score.
Leader Jacquelin defied strong crosswinds blowing in from the Indian Ocean to be the only player in the elite 36-man field not to drop a shot, the Frenchman carding a five-under-par 67 that featured three birdies in the last five holes.
He is one shot clear of Louis Oosthuizen, who has second place to himself.
Sharing third spot with Clarke is another Frenchman, Victor Dubuisson.
One stroke further back on two under is Simon Thornton. The County Down resident finished his round with a birdie.
Next best of the Irish is Padraig Harrington on one under, while Michael Hoey posted a 72 to lie on level par
Speaking after his round, Darren Clarke said: "My objectives are getting back to playing some of the golf I know I can play. I have had a frustrating last couple of years where I have not played that badly but made stupid mistakes.
"I took a look at myself in October and thought I was getting too fat so it was time to do something about it. I spend a lot of time in the gym and changed my diet and hopefully I will reap the benefits.
"I plan to keep doing what I am doing and maybe get stronger and stronger. I hit a drive on the tenth today of 300 yards back into the wind and another driver from 280 yards to the green and I couldn't have done that before."