"What impressed me so much," the six-time Masters champion wrote, "is that when he realized he was in a position to win, he finished it -- and that's the mark of a champion."
Nicklaus was far from alone in noting how the Englishman had pounced on the 16th tee, shortly after learning that Jordan Spieth's meltdown at the 12th had handed him the lead and left playing partner Lee Westwood in second. The contrast between Willett's own response (a superb tee shot to 6 feet) and Westwood's (a limp effort to the front of the green) was stark.
Willett, we assumed, was unexposed to the white heat of final-round contention in the majors, and yet here he was, stepping forward like a man who knew exactly how to react. Indeed, he had performed all day with great maturity, capitalizing on his good shots and coping with the bad. What happened on the 16th tee was not the start of his campaign, but the moment he grabbed the opportunity, he had spent all day earning.
It was almost as if he had been schooled in championship cut and thrust. Had he? Not quite. He was only a second-time visitor to the tournament who until that day had never broken 70 on the course. Instead, eight months earlier, at St. Andrews, during the final round of the 2015 Open Championship, Willett had his first brush with major contention and, perhaps even more tellingly, had the best seat in the house watching Zach Johnson win.
It had been a dramatic yet protracted Open, with Tom Watson's farewell in the dark, Spieth's brush with Grand Slam destiny and a Monday finish. So when Willett stood behind the R&A clubhouse after his fourth round, only a few curious media members were on hand to hear his rueful but positive thoughts on the 70 that left him tied sixth.
"We've been in contention pretty much from the get-go," Willett said. "I played some good golf. We're going to finish maybe 4 or 5 back so, you know, they can easily be picked up, so there's a lot of positives to be taken."
These are common words in the aftermath of a decent performance. What added significance was what happened next. As he prepared to step away, a final question was pushed his way: Had he felt comfortable out there?
Willett paused. Every now and then a player steps outside the pat demeanor of a post-round interview and says something with meaning. Willett did so then. As he voiced his thoughts, it was almost as if the truth of them was slowly dawning on him.
"I think it's good to play with someone like Zach today, who could potentially win it," he said. "I can actually look back and see how he won it, what he did, what he didn't do, and stuff like that I can learn from."
An hour later, Johnson, victor in the three-man playoff, was lifting the Claret Jug.
A week later, Willett won the European Masters.
Eight months later, his wife Nicole gave birth to their first son. They named him Zachariah.
A week later, he stood on the 16th tee at Augusta National, suddenly leading the Masters, apparently knowing exactly what he needed to do next.
Willett is not the first Masters champion to take a crash course in how to win.
Back in 1978, Severiano Ballesteros was a raw 21-year-old playing the final round at Augusta alongside 43-year-old veteran Gary Player. The youngster quickly found himself out of contention and the patrons assumed the old-timer was, too.
In his autobiography, Ballesteros wrote that on the 13th fairway, Player called him over. "Seve, I want to tell you something," he said, waving his club at the galleries. "These people think I can't win anymore, but I'm going to show them they're wrong."
Player completed the back nine in just 30 strokes to confound his critics (real or imagined) and win a third green jacket. When the final putt dropped, Ballesteros, awed by Player's never-say-die attitude, embraced him and said, "You have shown me how to win."
Two years later, Ballesteros found water at 12 and 13 during the final round. A 10-shot lead on the 10th tee was down to 3. Rattled, he heard a voice cry: "Come on, Jack!"
History was repeating itself. Ballesteros remembered Player's words, convinced himself the patrons were against him, rallied, and became the then-youngest winner of the Masters at the age of 23.
Six years later: Another young European (Sandy Lyle) was paired with another veteran (Jack Nicklaus) -- and produced another sensational back-nine victory march.
In his autobiography, Lyle relates that he heard Nicklaus suggest on the Saturday night that he would need a 65 or 66 to win. "To my ears," he wrote, "it sounded like an impossible dream for either of us."
Lyle then described -- in telling detail -- how Nicklaus performed that famous Sunday in 1986: How he withstood errors, took advantage of good fortune, admitted to nerves, joked with his caddie (son Jack Jr.) and utilized skill and courage to overcome the leaders. "I felt privileged to have the best seat in the house throughout the unfolding drama."
His ears might have doubted Nicklaus on Saturday evening, but on Sunday afternoon, they had no option but to believe: "I cannot overemphasize the level of noise. It was quite unlike anything I have ever experienced on a golf course before or since."
Nicklaus carded 65, set a target no one could match, won his sixth Masters at the age of 46 and left a legacy for Lyle, who concluded, "Having savored the atmosphere around the 18th green as an onlooker, it intensified my desire to experience it again in the future -- but next time as the centre of attention."
Two years later, he stood on the brink of history himself, needing birdie on the 72nd hole to become the first British winner of the green jacket. He found the fairway bunker, but he also found the bottom of the cup in three strokes. He'd learned well, and, as good as his word, the next time he was "the centre of attention."
It's possible that the Masters is uniquely susceptible for this type of inspiration, because no other championship plays quite so intensely on emotion and narrative.
The U.S. Open tests patience and demands a sort of serenity. In fact, being oblivious to the moment, rather than swept up in it, is an advantage.
The Open Championship is an examination of perseverance, unflappability (with weather, draw, bad bounces) and links expertise.
All of which is not to say that Augusta National is not a distinct golfing test. Clearly the fast greens, undulating terrain and exacting nature of approach shots cannot be overlooked.
But the Masters has a drama all its own, a consequence of the club, the media, the public and the players buying into the heightened emotion. In the circumstances, it's really not surprising that the roster of winners includes so many men driven in ways quite unlike those of the other majors.
Take Nicklaus in '86. Not only an inspiration to Lyle, but a man whose own motivation was a newspaper article that had written him off as "done, washed up and through."
Or Ian Woosnam, a man whose victory in 1991 links the experiences of Player, Ballesteros, Nicklaus and Lyle.
The Welshman arrived at Augusta that year fresh from reaching the top of the world rankings only to be told by a journalist that no world No. 1 had ever won the Masters. Like Nicklaus, he didn't much appreciate the nugget of information.
Nor was Woosnam too happy that his old friend Lyle, with whom he had played golf since the age of 12, was heading to the Champions Dinner alongside fellow Europeans Ballesteros, Nick Faldo and Bernhard Langer. It gnawed at him; he felt he should be there with them.
During the final round, he was distracted by a patron shouting at him, and the final piece of the puzzle was in his hands. Like Ballesteros and Player, he used his fury rather than allowing it to distract him.
What, too, of Mark O'Meara winning in 1998, 12 months after his close friend Tiger Woods had found success? Or Ben Crenshaw's emotional victory in 1995, days after the loss of his mentor Harvey Penick? Or even the fact that Phil Mickelson finally won at Augusta 12 months after "the wrong lefty" (Mike Weir) had claimed a first green jacket for guys who stand on the other side of the ball?
None of these men claimed success without decades of hard work on their long game, short game and putting. None lacked for mental or physical strength. None found themselves on that final green without withstanding numerous career highs and lows.
Yet at the same time, big doors swing on small hinges and our intimate knowledge of Augusta National is one of them. We know the eerie cry of the train whistle that echoes around Amen Corner. We know the silence of the 13th tee and the wall of noise around the 16th green. We know the Butler Cabin is a little bit peculiar, and we know the man who is fitted for a green jacket there will have a tale to tell.
We know it, we embrace it, and it inspires the competitors every bit as it inspires those of us watching.