The 39-year-old Ryder Cup star has enjoyed the finest year of his career to date and he is in pole position having racked up 12 top-10 finishes and won back-to-back tournaments this season in the Mercedes-Benz Championship and the Alfred Dunhill Links Championship.
His play in the four majors has also been exemplary having tied for eighth in the Masters Tournament, tied for fourth in the US Open Championship, tied for seventh in the British Open and tied for 20th in the US PGA Championship.
That has helped him amass total prize money of €2,695,248 ($3,447,490), nearly €300,000 ahead of second-placed Padraig Harrington.
The Irishman has had an even more spectacular year than Karlsson winning the British Open, where he was the defending champion, and the USPGA in a stunning few weeks in the summer.
To overtake Karlsson and succeed Justin Rose as Order of Merit winner, the 37-year-old Harrington, who also won the trophy in 2006, needs to finish first or second, on a course he is not comfortable on, and hope that the big Swede does not finish second.
The winner’s purse is €708,000.
Harrington, who was a teammate of Karlsson at the Ryder Cup in September, was quick to reject any suggestions that Karlsson would be an unworthy Order of Merit winner taking into account his own two wins in the majors that have propelled him to fifth place in the world rankings, one ahead of the Swede.
“At the end of the day, I haven’t played enough events to put myself out there,” he said.
“And in the events I played, I certainly didn’t show the form that I probably showed in the States this year. My best events definitely weren’t in Europe this year at all.
“I had a lot of top-five finishes in the States, but didn’t seem to have much form in Europe, and that’s why I’m not winning the European Order of Merit at the moment. Obviously, I need a big week this week.
“Robert has performed more consistently in Europe throughout the year, so consistency-wise, and that’s what an Order of Merit is, he probably deserves it.
“But that doesn’t mean he gets it. We have to wait until Sunday to sort that out.”
Lee Westwood of England and Miguel Angel Jimenez of Spain are also still in with a chance of finishing the year as European number one, but their chances are remote as they have too much ground to make up on Karlsson.
Other issues at stake include finalizing the top 15 players on the Order of Merit who will secure a place in next year’s US Open at Bethpage in New York, while the top 30 also qualify for The Open at Turnberry.