Henrik Stenson expects to be pushed "to the limit" by Danny Willett as the battle for Race to Dubai glory draws to a close.
Open champion Stenson is on course to finish as the European Tour's number one for the second time in four years, with two events of the season remaining.
The Swede holds a healthy lead over nearest rival Willett ahead of this week's Nedbank Golf Challenge in South Africa, but is aware the Englishman - runner-up to Rory McIlroy 12 months ago - could yet turn things around.
Willett won in Sun City two years ago and Stenson - the winner of the event in 2008 - said: "I'm sure Danny's going to try and find some game here for the last couple of weeks and push me to the limit.
"I've had a really good year behind me and it would be nice to finish it off with being Europe's number one.
"It's a great chance for me to stay in that number one spot, if I play some solid golf these last two tournaments. If I were to get anywhere near a win, or win one of them, then I would imagine it would be a done deal."
Willett, who won the Masters in April, added: "We've both got pretty good track records around this golf course, so it could be interesting.
"Me and Henrik have both had fantastic years, both picking up our first major and having good showings elsewhere around the world, and it now boils down to two events where I am back to chasing.
"I'm a little bit behind him so I'm going to try to make up some ground this week."