The playoff ended in a certain amount of controversy when Poulter dropped his ball on his marker when preparing to face a 30 foot birdie putt at the second extra hole but given that he faced that long putt for survival it was unlikely that the one shot penalty was ever going to alter the outcome.
For Karlsson the win completes a remarkable twelve months during which he has now been a two time winner and runner up on three occasions, one of those when losing a playoff to Lee Westwood in a PGA Tour event in Memphis.
Karlsson was forced to take nearly four months off tournament golf in 2009 with an eye injury caused by fluid behind the retina. This victory completes his comeback and given the strength of this week's field is sure to take him well inside the world top twenty from his current 36th position.
Karlsson birdied his first and second holes today and then holed an 8 iron at the third for an eagle and at that point he had snatched the lead off Poulter who had been slow to get his round moving forward. Poulter recovered with birdies at the 7th, 11th and 12th but despite bogeys at his 4th and 6th holes, Karlsson stayed in touch with birdies of his own at the 10th and 11th and one shot separated the pair with just six holes to play.
Lee Westwood would add to the already significant drama when he birdied the 14th, 15th and 16th to move within one of Poulter but while Karlsson was able to birdie the final hole Westwood could not and the playoff between Poulter and Karlsson began.
Both players hit delightful pitches at the first extra hole to set up their respective birdies and so it was back to the tee. This time, however, after Poulter had hit an ordinary pitch to 30 feet or so, Karlsson found his range again, finishing 4 feet from the hole. Poulter's mishap with his marker cost him any real chance and when Karlsson holed his birdie putt it was all over.
Alvaro Quiros and Lee Westwood were one shot back in a share of 3rd position while Rory McIlory finished alone in 5th position.
Martin Kaymer was unable to challenge for the World number one position but he today became the European number one in 2010 by securing the money list title. Kaymer finished 13th in this week's event but his brilliant season has earned him Ã¢Â‚Â¬4.4 million or US$6 million, the number three position in world golf and his first major championship.
Brett Rumford was the best of the three Australians this week when finishing 28th, Marcus Fraser was 32nd and Richard Green 48th.
Green has however finished as the leading Australian on the Race to Dubai rankings with earnings of Ã¢Â‚Â¬1.28 million and 21st position. It is Green's best year monetarily in Europe, narrowly ahead of his previous best in 2004 although that year he finished 17th in the money list ranking.
The next European Tour event is the first event of the 2011 season and will be played next week at the Alfred Dunhill Championship in South Africa.
Want video tips delivered straight to your inbox? Subscribe to iseekgolf.com newsletters.