Kaymer started the final round with a six stroke lead but that evaporated through first 12 holes. But after bravely birdieing the 72nd hole to force a sudden-death play-off with Dane Anders Hansen, the young German regrouped and played a sensational extra hole.
A huge drive was followed by an even better six iron on the par five 18th which came to rest just seven feet from the hole. With Hansen struggling, Kaymer safely two putted for an emotional home victory.
He said: The drive was really good and the second shot was, I think, one of the best shots in my career. And it was a very special feeling when I walked on the 18th to see all of the German flags in the background, truly amazing. It was a very, very special win.
Kaymers victory, his second on The 2008 European Tour International Schedule following his earlier success in the Abu Dhabi Golf Championship in January, provided a fitting celebration for the 20th anniversary of the BMW International Open.
The panel voted Colin Montgomeries approach to the tenth hole in the final round of the Open de France ALSTOM into second place in The European Tour Shot of the Month Award for June. The Scot, chasing a high finish and valuable Ryder Cup points, produced a wonderful approach to the tricky par four hole at Le Golf National which spun back to within inches of the hole for a tap in birdie which helped him secure second place.
Third went to Lee Westwoods third shot to the 17th green during the third round of the US Open Championship at Torrey Pines.
Previous monthly award winners were South Africas Richard Sterne (January), New Zealands Mark Brown (February), the Northern Ireland pair of Graeme McDowell (March), Darren Clarke (April) and Richard Finch (May).
The European Tour Shot of the Month Award is presented to the Tour Member for the shot judged to be the most outstanding played during each calendar month on The European Tour International Schedule. The winning shots from each month are entered into The European Tour Shot of the Year Award.