These days, Jack does not know what sort of day it is going to be until he slides out a leg from under a duvet and tests it on the carpet. Yesterday morning, when he applied pressure, there was no reaction. But plenty came later.
Nicklaus is 56 now, and the face looks as though someone has turned his colour knob down. When people reach that age, the operating instruction is usually to maintain warmth and keep happy, and Jack has managed both this week. Yesterday he warmed more than himself as he shot a second-round 66 to take him very close to the peak. He is in with a chance yet again.
The Golden Bear will no longer be a consideration for the Open the day he is nailed into a mahogany box, and even then you would not be able to rule the box out. It would be idiotic to suggest the man remains within the perimeters of his pomp, but with men like Nicklaus (and very few of them have ever been created) greatness lingers a long while. The American's talents are being whittled away, but almost like the erosion of the Himalayas, the change has come imperceptibly and with little significance.
"I don't think my standards are what they used to be and I can drive better than I did today" he admitted after yesterday's round. "My drives have to improve over the next two days because I can't keep on getting lucky.
"Every so often I will play some good rounds of golf if the conditions are right and I need these [warm] conditions for me to have a chance.''
It must be rather aggravating for Nicklaus to find himself being comprehensively outdriven as he was yesterday. In the old days, the local control tower had to be alerted when he stepped on to the tee. However, there are other gifts remaining in the locker, not least the sort of searing self-belief that could split an anvil.
"I am never surprised when I play well, just disappointed when I play poorly," the Golden Bear said. "I know what playing well feels like and I know what my game is like when I play well. I know how I am mentally and how my composure is and I am pretty near with those elements, even if I am not hitting the ball that well. I have to put all those things together.
"When I putt I can be a match for anyone and my problem the next couple of days will be managing myself, not my game. If I want to have a chance I have to drive the ball well.''
Jack acknowledged the input of the gallery, and the days when he was a plump tiro challenging Arnold Palmer and implored to "knock it in here fatty" on placards carried by spectators adjacent to bunkers now seem rather far off. If The Queen thinks the world smells of new paint because of the extensive preparations that precede her visits, then it may also be that Nicklaus does not know that applause is not a constant background noise in everyone's lives.
As the birdies stacked up yesterday, word got around and spectators, photographers and journalists started mobilising like termites on a picnic march. While Jack commanded this attention, it was possible to feel sympathy for his playing partners, Shigeki Maruyama and Gordon Brand Jnr.
The Japanese player acquitted himself well despite thrashing a bunker shot among the flasks and fairy cakes of those in a stand behind the sixth green, but the third man had a much less enjoyable day. The Scot put his ball in places where it became easy to comprehend why Brand rhymes with sand, but, despite his problems, he did not liberate the gin bottle from the cabinet and run a hot bath last night. He was just pleased for Nicklaus. "Jack may be 56, but he is by far the best golfer I have ever played with and the nicest man," he said. "Any golfer, of any age, would have been proud of that round today.''
Others, it seems, will continue to get the privilege of his company. "When you are playing well and in contention, and that's what I come over for and have done for 40 years, it's good," Nicklaus said. "I enjoy coming if I can compete and that has always been my criteria. I don't think I will play when I am a ceremonial golfer. I thought I was getting close, but ceremonial golf is far off this week.''
Even when Nicklaus does go, he will leave behind the legacy of 18 majors and the most successful golfing career the world has ever seen. But for the tens of thousands who have congregated at the Royal Lytham shrine this week, there was at least one salutary message yesterday suggesting the infuriating game is not the fulcrum of everyone's lives.
It came on the par-four eighth, where the bordering Preston to Blackpool South railway line had been closed down for the morning. A rail worker, a middle-aged chap with glasses and a ponytail he must have borrowed from a younger relative, was recording the caravan of players tramping before him on a video camera.
As he ushered visitors across the line he wore a luminous orange jacket, which was strange, firstly because there were no trains, and secondly there was the sort of stunning brightness around that attacks the eyes when you emerge from a summer matinee at the cinema. "You see those three down there," our man asked, pointing to a slim Caledonian with a moustache, a squat Oriental and a legend. "Which one is Jack Nicklaus?''Reuse content