Kjeldsen took a two-shot lead into the final round and was one shot ahead with??two to play despite being four over par for the day, as the players battled winds??gusting up to 40mph in another round of tricky conditions at Royal County Down.
A three-putt bogey on the 17th left Kjeldsen needing to birdie the 18th to win??his fourth European Tour title, but after chipping from one side of the green??off the other, he did well to get up and down for a closing 76 to join a play-off alongside Bernd Wiesberger and Eddie Pepperell.
The players returned to the par-five 18th for the first hole of sudden death??and Kjeldsen was the only one able to find the green in two, before two-putting??for a winning birdie.
Kjeldsen had seen his overnight lead wiped out on the opening hole after he dropped a shot and playing partner Max Kieffer made birdie. Despite bogeying the next, a run of five pars was enough retain Kjeldsen???s advantage as the strong wind sent scores soaring, but slipped back again with a double-bogey at the eighth.
The Dane two-putted the par-five 12th for his first birdie of the day, but missed the chance to move two clear when he three-putted the 14th for bogey.
Wiesberger recovered from a dropped shot at the 15th to stay within one of the lead by holing a long putt from over the 16th green, as Pepperell closed his blemish-free round to set the clubhouse target at two-under.
The Englishman, beginning the day seven shots adrift, crucially saved par on the 17th after finding a fairway bunker off the tee, but twice tangled with heavy rough on the 18th and had to settle for a par five.
???I played really well, so I have to credit my putting for no bogeys,??? Pepperell said. ???I think all four days have been tough, so whilst today was very difficult it didn???t feel all that different to what we???d played in the first three days.
???I said to myself anything in the 60s is a really good score, and once I got to two under I kept trying to tell myself the same thing.???
While Carbera-Bello???s hopes ended with dropped shots at the 15th and last, Wiesberger saw an eight-foot birdie chance at the 18th to move to three under slip millimetres wide of the cup.
That left Kjeldsen just needing to par the last two holes to take the title, but he three-putted the 17th and needed to nudge in a four-footer at the last.
Danny Willett had set the early clubhouse target with a three-under 68 to end level par for the week alongside Andy Sullivan, finishing in style with a chip-in eagle from the right-side of the green.
The group a further shot behind included Saturday???s course record breaker Max Kieffer, who closed the week with a six-over 78, with Matt Fitzpatrick posting his first top-ten finish since January.
Rickie Fowler???s Irish adventure ended in a tie for 30th, with Graeme McDowell posting back-to-back birdies late in his round to also finish seven over.??