By Dan Reardon

Ninety years ago, two 15-year-olds were matched up against each other in a competition to determine the best caddie at Glen Gardens Country Club in Texas. Young Byron Nelson and Ben Hogan went 19 holes before Nelson prevailed, and one of golf’s great rivalries had begun. Factor in one more 15-year-old from West Virginia, Sam Snead, and you had golf’s Triumvirate, who would rule the game for at least two decades.

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Fifty-five years ago, a young professional named Jack Nicklaus teed it up at Oakmont Country Club in a playoff for the U.S. Open Championship with the game’s “King,” Arnold Palmer. Nicklaus won to launch at least a decade of debate about the game’s top player.

In 1997, just 20 years ago, a young professional showed up in Augusta, Georgia at the Masters and disassembled the record book and began a decade-long dominance of the PGA Tour with his only potential rival Phil Mickelson. Insiders will tell you Tiger Woods never considered Mickelson his rival, and Mickelson always felt the unspoken disrespect Woods had for his place in the game.

This week in Chicago, two 24-year-olds will begin the second-to-last stage of the Tour’s FedExCup Playoffs, and many think Jordan Spieth and Justin Thomas are at the outset of one of the game’s next great rivalries.

While the rivalry is no doubt in place; the race to anoint each with greatness may need some seasoning. Spieth, with his 11 career wins spanning his four years on Tour and his validating third major title at the Open this summer, would have the strongest argument for predicted greatness. Thomas has authored a spectacular 2017 season with a brilliant finish already in place. But this is the only notable year on his resume.

One only need to look back two years ago, when an equally brilliant stretch by Jason Day had people carving his bust for the World Golf Hall of Fame. Day has spent much of the time since trying to get another win.

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Many years have already elapsed in the Spieth-Thomas rivalry. Both recount the first time they squared off, at 14, for a championship in an AJGA event, with Spieth recording the win. But the relationship between these two young talents is unique at this stage as they vie for success. They are friends much more than they are rivals, and they take very measured steps in addressing a rivalry.

Following his win in Boston, Thomas admitted that seeing Spieth and others in their age group enjoy success is fuel for his own ambitions. “I still get jealous. Any time any of my friends win and I don’t, I’m extremely happy for them, I’m pumped for them, I’m excited, but I’m jealous. I wish I had three majors right now. I mean, I’m obviously pleased with one, but I wish I had three.”

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“I wish that I holed out a bunker shot at Travelers to win,” Thomas continued. “And the same works for, I’m sure, them with me. It’s a weird little kind of thing, but we’re all excited and happy for each other. But like I told you… it definitely puts a little bit of fire in. I felt like I was getting behind but at the same time, I was just starting, and I can only do as much as I could do.”

During his recent run, he has been baited into declaring himself the best player in the game. And on each occasion, he has wisely pronounced that answering that question serves him no purpose and declined.

Spieth sees the relationship in much the same light. “I just think we grew up together. I think that happens with the people that — I mean, you grow up and you watch each other work from when you’re 14 years old. We roomed together when we were 14 years old. He’s one of my best friends in the whole world. I would say we’re very close friends, just because of the time we spend on and off the course together in a pretty unique position at our age in what we do for a living.”

As Spieth continued, “we can share experiences with each other that we can’t really describe or explain to anybody else that’s our age, or very few, I should say, and it creates a unique relationship.” And he will add that he still has his eye on the prize and would love to finish with a flourish in the FedExCup Playoffs and make the conversation for Player of the Year worthwhile. “It’s an MVP. It’s an MVP award. You are the best player at what you do at the highest level. So it’s extremely important. It’s the most important end-of-the-season award I think you can win.”

And then there is the oddity of Spieth’s caddie, the highly visible and regarded Michael Greller. Before he joined forces with Spieth, Greller had caddied for Thomas as an amateur and admits that if Thomas had turned professional before Spieth, he likely would have ended up on Thomas’s bag.

Regardless of how the fortnight of the FedExCup plays out, the talented twosome has an opportunity to do something their rivalry predecessors rarely accomplished. Presidents Cup Captain Steve Stricker will be pushed to pair them in the team competition, as may be the case the following year in Paris at the Ryder Cup.

Hogan and Nelson never were partnered in the Ryder Cup. Palmer and Nicklaus were only once, winning their match. And Woods and Mickelson will always be remembered for the fractious two matches in 2004 at Oakland Hills, where the only thing worse than the way they played was the rapport between to two.

Spieth and Thomas can set a new rivals tone for history.

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Dan Reardon has covered golf for radio station KMOX in St. Louis for 33 years. In that time, he has covered more than 100 events, including majors and other PGA, LPGA and Champions Tour tournaments. During his broadcast career, Reardon conducted one-on-one interviews with three dozen members of the World Golf of Fame. He has contributed to many publications over the years and co-authored the book Golf’s Greatest Eighteen from Random House. Reardon served as Director of Media relations for LPGA events in both St. Louis and Chicago for 10 years.