On his way to winning the 2017 British Open, Jordan Spieth drew on deep reservoirs of resilience.
He also took advantage of the rules.
Let's look at how he worked within the letter of the law.
The shot that set the plot in motion was Spieth's wild drive on the long par-four 13th, which sailed into a nasty tangle on a hay-strewn dune.
Rather than proceed from that gnarly lie, Spieth declared his ball unplayable, which, under Rule 28, offered him three options for relief.
One option was to proceed under the stroke and distance provision. Translation: He could have gone back to the tee and reloaded. (On the NBC telecast, Johnny Miller said he thought that this was Spieth's best bet; Spieth didn't think so, and he now has more major wins than Miller).
A second option was to drop his ball within two club-lengths of where it lay, no nearer to the hole. But that made little sense, since it still would have left him playing his third shot from a sloping lie in the spinach.
Spieth decided that his third option was best. That was to drop as far back as he liked, on line with the flagstick and where his tee shot had landed.
"I just asked the question, 'Is the driving range out of bounds?' And I got the answer, 'no,' Spieth said after his round. "And I thought, Well, then, that's a much better location for me to hit the next shot because I can get it much closer to the green and it saves me almost a full stroke from going back to the tee."
Sounds simple, right? But he still wasn't done, because going back on that line in search of relief took Spieth into one of the equipment trucks parked along the far edge of the practice range. The good news for Spieth is that those equipment trucks qualified as temporary immoveable instructions, which, under Rule 24-2, entitled him to line of sight relief.
In other words, he got to drop away from the trucks, more than one club length but within two, onto a flat lie on the practice range, which was treated as being in play during the championship, just as it is for Royal Birkdale members throughout the year.
Got it? Good.
Finally, there was the matter of actually hitting the shot.
"Michael [Greller, his caddie] told me, 'No 3-wood, hit 3-iron.' And I hit it, thought it was right. After I struck it, I didn't like it because it wasn't where we were trying to hit it, but I had some room, given the club I had and the yardage I had, which Michael was right on, fortunately."
The rest is history.
Spieth got up-and-down for bogey on 13, then set off on a birdie-eagle-birdie-birdie stretch and victory.
It was scintillating golf.
But as David Rickman, the R&A's director of rules and governance put it, it was also a "smart use of the rules.”