Everyone who's followed golf at all has had that moment when they realise the man they've been watching for 18, nay 72, holes is in fact either totally bald or else on an inexorable journey towards baldness.
The cap that's been plastered onto their cranium for the past four hours is concealing not their luscious tresses but a rapidly receding hairline.
The NZ website Stuff did ponder whether it was those very caps that were to blame for the apparent epidemic on the PGA tour. Trichologist Leonora Doclis attributed it to the stress golfers are under.
It may be that the link between golfers and hair loss is that they are under so much pressure to win that their hair loss accelerates, as stress is known to trigger genetic hair loss in those who are predisposed to the condition.
Here are a selection of the golfers that have produced that reaction in fans. Indeed, some of you may have been unaware of their follicle situation.
Thomas Bjorn
Stewart Cink
Jim Furyk
We all know now he's bald. But the first time, the first time...
Tom Lehmann
Watched him canter to an Open Championship victory after a smashing weekend's golf at Lytham in 1996. He pushed by Paul McGinley who held a 36-hole lead by the way. Only realised he was bald after he tipped it on the 72nd hole.
Matt Kuchar
Steve Stricker
He doesn't let the cap off his head but his hair is thinning away to nothing on the top.
Jordan Spieth
Not bald now. But it's in the post.