Martin Kaymer has earned the final spot of the year in what is arguably the most difficult tournament to qualify for, the PGA Grand Slam of Golf, which will be held at Port Royal Golf Club in October.

Also invited will be Phil Mickelson, who won The Masters in April, Northern Ireland's Greame McDowell who claimed the US Open in June and last month's Open winner Louis Oosthuizen.

First, Kaymer had to survive the deepest field of any major championship.

Then, he had to conquer the long, demanding, bunker-filled test of golf that is Whistling Straits.

And if that wasn't enough, the 25-year-old German had to endure a three-hole playoff with long-hitting, crowd favorite Bubba Watson.

Such are the obstacles standing between competitors at the 92nd PGA Championship and a berth in the hardest tournament in the world to qualify for - the PGA Grand Slam of Golf.

But survive, conquer and endure Kaymer did, beating Watson in that playoff and winning the PGA Championship.

In so doing, Kaymer punched his ticket to Port Royal Golf Course in Southampton, Bermuda, with the final berth in the major-champion foursome that will decide on Oct. 18-20 who will be the Champion of Champions.

"I don't realize what happened," Kaymer said. "I just won my first major. I've got goose bumps just talking about it."

Kaymer earned $1.35 million, went to third in the Ryder Cup standings for Europe and moved to a career-best No. 5 in the world.

Kaymer continued the trend of first-time major winners that began at June's U.S. Open with Graeme McDowell's victory at Pebble Beach and moved through Louis Oosthuizen's seven-shot victory at St. Andrews in the Open Championship.

He fired a final-round 70 to Watson's 68 as both finished 11-under-par.

Then, Kaymer beat Watson 11-12 in the playoff after Watson double-bogeyed the playoff's final hole - No. 18.

It's also a foursome with international flavour.

Along with Kaymer, a native of Dusseldorf and the first German to capture a major championship since Bernhard Langer won the 1993 Masters, the PGA Grand Slam of Golf features American Phil Mickelson, McDowell from Northern Ireland and the South African Oosthuizen.