He had just made history as the first teenager to win on the PGA Tour in eight decades at the John Deere Classic in Illinois, giving the prodigious talent a last-minute ticket to Muirfield.
It was late on Sunday night, but Spieth – with the adrenalin pumping and the opportunity of a lifetime in front of him – hopped on a plane bound for Scotland, landing on the Monday morning of Open week.
His first taste of the game’s oldest major came in a three-ball alongside fellow American Russell Henley and Matthew Fitzpatrick, an amateur from Sheffield who was at the start of a golden summer that ended in him winning the US Amateur.
It was a three-ball that offered a glimpse into golf’s future, one played in front of two dozen members from Hallamshire who had followed Fitzpatrick up north and Spieth’s immediate family from Dallas. The round was played in good spirits, too, exemplified when Fitzpatrick pushed a shot into the rough and Henley chased after it in an attempt to ensure his playing partner’s ball was not lost.
After two days Spieth had beaten his playing partners by six shots. Four years later he would beat the entire Open field by three strokes.
Spieth arrives back in Scotland this weekend for his sixth crack at an Open Championship as its defending champion. His victory at Birkdale last year was the third major triumph of what has been a sparkling career, more successful in terms of grand slam titles won than all but 28 men who have played the game.
But there is no arrogance about him, just a humility that, allied to a putting stroke that when hot has no equal and one of the strongest mentalities in any sport, has created one of golf’s most respected individuals.
Certainly, when speaking about being Open champion his pride is obvious, even when talking to him from across the Atlantic Ocean.
“The title Champion Golfer of the Year is such a cool title,” he says. “It doesn’t get used over here on the PGA Tour, so I’m looking forward to having that announcement again as I get on to the tee.
“Last year when the words Champion Golfer of the Year were spoken on the green at Birkdale it just kind of hit me. It was almost like someone had punched me in the gut in the best way possible.
“You need to realise how special this is and embrace what it means. I look forward to teeing it up at Carnoustie, having those chills go through me as I step to the first tee and remember the year before, and obviously get focused and try to do it again.”
Current form would suggest he may struggle. Spieth has not won a tournament since last year’s Open, the longest drought of a career that saw him cram 14 worldwide wins into four years.
That nerveless putting stroke, whereby he would seemingly drain anything within 15ft of the hole, has temporarily deserted him. “It’s been an off-year this year,” he concedes. “The results haven’t been up to my own expectations, and it’s been the putting.
“I’ve been working so much on that that it started to – as I knew it would – come around and I’m starting to hit my lines better and see my lines better. But then the ball-striking has taken a little bit of a back seat.
“Whether everything’s firing or everything’s just decent, I’m starting to see everything rise up. I’ve put in the hard grind leading into the Open. I have no doubt in my ability to come back and defend whether form’s on, off or anything indifferent.”
Fluctuating fortunes are not uncommon for a golfer, even during the course of one round.
At Birkdale last year Spieth led or had a share of the lead after every round. By the time he stood on the 13th tee on the Sunday playing partner Matt Kuchar had wiped out the three-stroke advantage with which he began the day.
Spieth pushed his tee shot, searched for the ball for five minutes and then had to take a penalty for an unplayable lie.
The subsequent recovery shot created the chance to drop just one stroke and then he followed that up by nearly holing his tee shot on a driveable par-4.
It was the response of a true champion, not following one bad shot with another, after which Spieth never looked back – even if reflections on that moment of panic remain vivid.
“I don’t remember exactly what happened on that tee shot,” says Spieth, who on his return to Dallas the following day fast-forwarded the coverage straight to that moment of truth. “For me it went by pretty quickly because it was, ‘okay, decision here, now I need to drop here’ – but with the coverage, with the commercials, it seems like a long time. That was tough to watch.
“From there it was the whole regrouping and remotivating and resetting a goal, and all that kind of took place pretty quickly.”
Therein lies the strength of Spieth – his mentality. In that 20 minutes of real time Spieth lost control then won the tournament all over again, with his six-iron on the 14th the shot he recalls as the one that mattered most.
In banishing the memories in an instant he also exorcised the demons of 15 months earlier when he had a five-shot lead stood on the 10th tee at the Masters only to drop six shots over three holes and present Sheffield’s Danny Willett with an opening the Yorkshireman barged through to take.
“I’ve kind of had a career’s worth of experience in four years, which I think is advantageous going forward,” reflects Spieth. “Last year’s Open was a similar type of situation to, say, the ’14 and ’16 Masters where I had control through seven holes in one and 11 holes in the other before it fell out of my hands.
“Having a positive experience of losing a lead and being able to regain it within a major championship Sunday is one that not many people have.
“I wasn’t trying to do it, but going forward I can certainly look back on that as positives coming out of what seems like a day that’s not going my way. All you need is a little bit of that kind of belief.”
So how does he do it? How does a player who was quicker to three major titles than Tiger Woods possess such a winning mentality?
“It is a grind,” he admits. “As much as you can throw out the noise; as much as you can stick to what you love to do, playing the game, accepting the challenges, and not thinking about what it means to you or to anybody else, and just play it because you love to play. That’s the toughest thing to do for us when tournaments are blown up.
“We are playing ourselves and the golf course, and that’s what we’re focused on. It’s just that it’s sometimes very difficult to throw out, especially when you get into majors because you grow up looking at the praise people get from it and the life-changing aspects that come with it and the place in history and you want that, and that sometimes can impact the way you feel and get you away from your normal game and create the drama.”
And so to Carnoustie, one of the toughest courses on the Open rota.
“I know Carnoustie presents, especially in the finishing holes but really throughout the entire golf course, a tremendous challenge, one that’s tough, but fair.”
And one the Champion Golfer of the Year will relish.