At the 99th PGA Championship, Jordan Spieth for the first time will be playing for one of the transcendentprizes in golf: the career Grand Slam. Of course, the 24-year-old is quick to deny hes thinking that way. Spieth insists his focus will be on simply winning the PGA, which, since his victory last month at the Open Championship, is now the only one of the four professional majors he hasnt won. I mean this, he intoned last week at Firestone in explaining his mindset. Its just a major.

Then again, Spieth, who because of his back-nine heroics at Royal Birkdale is occupying the same kind of attention in the golf public consciousness as he did when he won the first two majors in 2015, is floating on a cloud of confidence and well being. Free rolling, as his caddie, Michael Greller puts it. Its the approximate state that three of the five greats who achieved the career Grand Slam were in the year they captured the final leg, given that Ben Hogan in 1953 and Tiger Woods in 2000 each won three major championships, while in 1966 Jack Nicklaus won two.

So while Spieth may insist that because he expects to play in 30 future PGAs, if he doesnt win at Quail Hollow, its not going to be a big-time bummer whatsoever because I know I have plenty of opportunities, theres a chance he may never have a freer roll. And for the record, the last three winners of the Grand SlamGary Player, Nicklaus and Woodsall completed the feat in their 20s. For that matter, golfs first Grand Slammer, Gene Sarazen, won his first two majors at age 20, sooner even than Spieth. In the journey to the career Grand Slam, the time to take advantage of a head start is always now.

If all this sounds a bit over-caffeinated, its because career Grand Slams in golf are special. They are more rare than in tennis, where eight men (the latest Novak Djokavic) have done it. But more importantly, it can besad to see great players fall one major short. Counting Spieth, 12 players have achieved three legs without getting the fourth. And those for whom valiant attempts at the final have been thwarted by bad luck or multiplying tension or bothespecially Sam Snead with the U.S. Open, and Arnold Palmer and Tom Watson with the PGAhave ended up on a slightly lower tier of the pantheon. It looks like that has happened to Phil Mickelson in his quest for a U.S. Open, and that there is an increasing possibility of this happening to Rory McIlroy at Augusta National.

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Not that the career Grand Slam is a perfect measure of greatness. Walter Hagen, who won 11 major championships, didnt have a real shot at what evolved into the Grand Slam because the Masters wasnt even played until he was well past his prime. And what of Bobby Jones original Grand Slam in 1930, winning the U.S. Open and Amateur and their British counterparts in one year, which has never been replicated by any golfer over an entire career? That feat, or the still unattained the calendar professional Grand Slam, or even the Tiger Slam of 2000-01, would all have to be more exalted than the career Grand Slam.

In the journey to the career Grand Slam, the time to take advantage of a head start is always now.

Still, other than those one-offs, theres a good argument that theres no marker in golf better at historically differentiating the best from the rest than the career Grand Slam. It requires some special things. Theres the tennis analogy of the complete game in four different conditions especially the Masters, U.S. Open and British Open. (The PGA might be the favorite set up of the tour pros because its still U.S. Open light).

Then theres overcoming the pressure of finally capturing the last leg, which builds the more years that go by. Even Spieth was attuned to this challenge, conceding that he would have to be careful not to make the PGA an obsession. The con, he said of being just one major away from the career Grand Slam, and what makes it more difficult than just saying its another major, is that its one a year now instead of four a year that that focuses on, if thats what the focus is.

Clearly, getting the final leg is a validator. It means meeting the moment, demonstrating the rare ability to bring out your best golf when it means the most, when the pressure is highest, when the battle is hardest. It takes greatness.

That said, not all career Grand Slams were created equal. Heres how I would rank them, counting down from least to most significant:

5. Gene Sarazen Though he will always be a giant figure with seven major championships, Sarazen is golfs greatest beneficiary of retroactive history. Not only did he win the 1935 Masters by getting into a playoff on the wings of holing a 4-wood from 235 yards on the 15th hole on Sunday, but the Masters was far from being considered a major championship, probably not reaching that status until Ben Hogan and Snead played off in 1954. There was no pressure on Sarazen because he didnt even know he was making history.

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4. Gary Player Indisputably the games greatest international golfer, with nine majors included among his 159 victories worldwide, Player was ruthlessly efficient in clicking off the four majors in six-year period that ended with his victory at the 1965 U.S. Open at Bellerive, in the only time he would win that championship. Its quite possible that no one ever wanted the achievement more. I was aware of the Grand Slam in 1953 because Hogan was my hero in golf, Player said by phone last week, and I knew when he won at Carnoustie he had the four.

The prize was in his head when he won his first major at the 1959 Open Championship, and soon he became determined to beat rivals Arnold Palmer and Jack Nicklaus to the mark. Though he hadnt won a major since the 1962 PGA, he was primed at Bellerive. I was squatting with 325 pounds, the fittest I ever was in my life, Player said. He was going to a church in St. Louis every day and praying for courage. He wore the same black shirt every day, washing in the sink of his hotel room each night. When he got to the course, he devoted a few minutes to standing before the scoreboard, which had past winners names, and envisioned his own. I saw Gary Player, winner, 1965, and Gary Player winner of the Grand Slam, he said. I dont know if any golfer ever, ever, was as focused as I was that week on winning.

And if Player had lost the playoff to Kel Nagel, does he think he might have suffered the same frustrating fate in the U.S. Open as Snead? Oh, no. I would have won it, absolutely no doubt, he said. Of such minds are career Grand Slam winners made.

3. Jack Nicklaus The man who would go on to win the equivalent of three career Grand Slams achieved his first one as a forgone conclusion, he was clearly so good. But even Nicklaus confesses an early setback in 1963 at Lytham, where he bogeyed the final two holes to lose by one, created a crisis of confidence in his ability to win the Open Championship. With three legs of the Slam completed, he finished second at St. Andrews in 1964, and still wondered if his high ball flight would always hold him back on the windy linksland.

He seemed to find the key at Muirfield in 1966, but with a three-stroke lead with seven to play, he three-putted from seven feet, missing a 15-inch putt. I experienced one of the most severe mental jolts Ive ever suffered on a golf course, Nicklaus confessed in his autobiography. Jittery is not a strong enough word to describe my feelings. He bogeyed two of the next three holes, but then, as Spieth did at Birkdale, found a way at the 11th hour to go from negative to positive and eeked out a one-stroke win.

Realizing he had won the Slam, Nicklaus was overcome at the trophy presentation. He wrote: Being about to receive something that even I, never much of a self-doubter, had genuinely doubted would ever be mine, was extremely emotional. From that point, the Open Championship became the major where Nicklaus most consistently contended.

2. Ben Hogan True, the professional Grand Slam hadnt yet become a thing when Hogan won his fourth leg at Carnoustie in 1953 at age 40. In fact, Hogan, who hadnt won the first of his nine majors until he was 34, wasnt thinking career Grand Slam when he made his first trip to the Open Championship. He had gone because friends had urged him to for the good of the game, and for the challenge. Once there, he became engaged with a monastic purpose that entranced the Scots, keeping legs battered by his car accident functioning through long, soaking baths, mastering the nuances of the small British ball and stoically executing with near perfection. His victory remains perhaps golfs supreme example of a one-shot, do-or-die, all-or-nothing, surgical strike that culminated in a glorious mission accomplished. It earned Hogan a ticker-tape parade when he returned to the U.S., and turned out to be his final major-championship victory.

1. Tiger Woods Until further notice, his is the most brilliantly dominating career Grand Slam. Its Himalayan peaks remain prominent on golfs landscape: the 1997 Masters (by 12 strokes), the 2000 U.S. Open (by 15 strokes) and the 2000 Open Championship (by eight strokes). But it was the 1999 PGA at Medinah where Woods seemingly inevitable ascendance could have been stalled, and the tricky, seven-foot, left-to-right par putt he made on the 71st hole to maintain a one-stroke lead over Sergio Garcia may go down as the most important putt of Woods career. Any pain Woods suffered in his few close loses in majors for the first 12 years of his career was negligible, but losing at Medinah probably would have left a mark. With appropriate theater, Woods closed out his first Grand Slam with a triumphant march up the 18th at St. Andrews.

If Spieth can claim a fourth leg at Quail Hollow, where would his Grand Slam rank? Third best, behind Woods and Hogan.

Spieth, as the sixth holder, would be the youngest, by eight months. Hes been more stalwart than opportunist, having led or been tied for the lead in 15 of the 70 major championship rounds he has played. But other than his first major win, a wire-to wire job at the 2015 Masters, Spieths victories have been tight ones in which, for all his magic with the short game and putter, his tee-to-green play has lacked the majesty of Woods or Nicklaus or Hogan. Hes also lost the lead late at two Masters, leaving more scar tissue at an early age than Woods, Nicklaus or Player experienced.

Then again, Spieths combination of passionate competitiveness and personal charm is reminiscent of Jones, and engenders a similar degree of public devotion. If he could close out the Slam in Charlotte, his resultant popularity would lift golf and his persona into Jones/Palmer/Woods territory.

It would also install him firmly on the games throne at an early age. Nicklaus and especially Woods showed such a position can be a self-perpetuating mental edge. As good as being No. 1 in the world is, its betterthrough an early career Grand Slamto have proved youre the best when it matters most.

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