Sure, most of the world's top golfers were a continent away preparing for Muirfield and this week's British Open. And yes, even Spieth knows luck was one of the major reasons why he became the first teenager in over eight decades to win on the PGA Tour.
Spieth's ascension, however, isn't a fluke.
The 19-year-old Texan simply affirmed why many view him as one of the world's most promising young golfers.
Spieth rallied from as many as seven shots down Sunday and took down Zach Johnson—a Masters winner and a defending champion playing in his hometown event—to notch his first career PGA Tour win in a grueling five-hole, three-man playoff.
He did it by thinking like a kid—and playing like a future star.
"This is my view on it, which is a 19-year-old's view, so don't hold me to it in a few years. But my view on it is you want to approach it the same way I approach being in contention in a college event," said Spieth, just a year removed from a one-and-done career with the Longhorns that he finished as an All-American. "If you start thinking ahead, you start thinking Augusta, you start thinking playoffs, you start thinking winning, it's difficult."
It's hard to not start thinking ahead to the Masters, the FedEx Cup and more victories for Spieth after his run through the par-71 TPC Deere Run.
The Dallas native, who was tied for second in Puerto Rico in March, opened the tournament with a 1-under 70.
The one stroke everyone will remember was certainly fortunate—and undoubtedly gutsy.
Spieth was in a deep bunker to the right of the green on No. 18 at the end of regulation. Though there were groups ahead of him with golf yet to play, Spieth knew he probably needed to hole out to have a shot at a playoff.
Spieth fired the ball at the pin. After a quick bounce, it pinged off the stick and dropped straight down in one of the more memorable shots in tournament history.
Spieth then survived four holes in the playoff with Johnson and David Hearn before sinking a 2-footer for the win.
"Now given, there was some luck involved. But to pull off the shot, it wasn't a winning feeling, per se. The only winning feeling came after the 2-footer went in when I made sure that it stayed in the bottom of the hole, and didn't somehow get out," Spieth said. "No, it was just shock, surprise, really cool atmosphere and cool roars. I didn't know how to react."
Spieth can be forgiven for that.
What he accomplished was essentially unprecedented in the modern game.
Spieth, who doesn't turn 20 for another two weeks, is the first teenager to win since Ralph Guldahl took the Santa Monica Open in 1931. To put that in perspective, Tiger Woods, Phil Mickelson and Rory McIlroy were all older than Spieth when they picked up their first victories.
Of course, to expect Spieth to match any of those star golfers in Muirfield this week would be unrealistic given his lack of experience.
Still, the way Spieth earned his ticket to the British Open suggests that he might be more ready for that challenge than some might believe.
"He's mentally strong ... it looks like he's pretty gathered. He's confident. He hit some great shots, obviously," Johnson said.
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