Tiger Woods returns this week from the longest break in his golfing reign to face what is unarguably the biggest threat to his pre-eminence. An absence from competition of nearly 10 weeks is no way to prepare to put a great pretender in his place. Not when Phil Mickelson is in this form, on this run, looking this real.
In fairness, the world No 1 has something of an alibi as to his whereabouts since the Masters. The loss of a father is an important moment in all but the most unfortunate of lives, but in Tiger's it was seminal. Regardless of the sentiment that will inevitably pour forth should the grieving son prevail on Father's Day, from a purely sporting perspective Tiger's reaction to Earl's death will define this US Open, and perhaps even his career.
Should Mickelson be allowed to win his third major in succession and so set up the "Mickelslam" at Hoylake, then Woods' hegemony will suddenly have a rival that appears menacing both on fairway and in record book (and even if Woods has not always had his own way on the former, he certainly has in the latter). Mickelson would become the fourth man to hold three majors at the same time - Woods, Jack Nicklaus and Ben Hogan being the others - and at a total of four his major count would be making further inroads into Tiger's mark of 10.
Incredibly, all of them would have come in the last 10 majors, while in that Tigeresque-period the man himself would have collected only two. What have they always said about Woods' dominance being a one-off, never to be repeated in this ever-so- competitive modern era?
And maybe it will prove so, pleasing legend lovers everywhere, as Mickelson has not only to negotiate his now shrewd path around Woods and 154 other Tin Cup wannabes, but also around Winged Foot.
At 7,246 yards, the monster of Mamaroneck is the longest layout which has ever been used for the most demanding major of all, and at 514 yards will boast the longest par-four hole in major history, although the New York course's sinister nature will not manifest itself most obviously in distance.
"I'm going to make a prediction," said Mickelson by way of explanation last Wednesday. "Next week somebody will hit the wrong ball out of the rough. There are not just hundreds, but thousands, of members' balls hidden in there that you just can't see, even if you're stood over them. It's thicker and denser than I've ever seen rough."
Cue the moans and groans that have served as a constant backing theme to the USGA's annual horror show. The much-maligned body will excuse themselves with their new policy of graduated rough (six feet of "intermediate" up to 1 1/2in deep; 12 feet of "primary rough" up to 4in; "secondary rough" up to 6in extending all the way to the ropes) and slower greens (12 1/2 on the stimpmeter - veritable rice puddings for the USGA) and claim they have thus guarded against a repeat of 1974 and the famed "Massacre of Winged Foot", when Hale Irwin's winning score was seven over par.
Mickelson does not foresee it being that bad. Not quite. "Winged Foot is so difficult that you don't have to do ridiculous things to make par a good score," he said. One fairway is just 20 yards wide, the most forgiving 28 yards. "And not only that but there are so many doglegs," said Mickelson. "You can't just step up and crank on it and have it go 330 [yards] down the middle. You have to carve and work your tee shots with the angle of the hole."
For that purpose Mickelson - who will turn 36 on Wednesday - has had a driver designed especially, weighted for control rather than distance, and he is veering to employing that single weapon of telling pragmatism rather than using the two-driver philosophy which worked so effectively at Augusta.
It is a quandary Woods would be envious of right now as he worries whether his game can possibly be match-fit. His nemesis expects it to be. "For anybody else on Tour, coming off such a break would be a real challenge, but for him the same rules don't apply," said Mickelson. "I don't think it's going to be a problem for him - unfortunately."