How many pints of Guinness can you fit in the Claret Jug?
We're just 18 holes from finding out as Ireland's Shane Lowry takes a four-shot lead into the final round of the 148th Open.
The 32-year-old carded one of the great major rounds - a bogey-free 63 - to reach to 16-under for the championship and take a four-shot lead into Sunday.
Lowry, making his eighth Open start, picked up shots at three of his last four holes to put clear daylight between himself and nearest challenger Tommy Fleetwood. Had a birdie putt at the last not come up just a few inches short, the engraver would surely be getting a phone call.
Lowry's playing partner, JB Holmes, is two shots further adrift in third place on ten-under, with Brooks Koepka and Justin Rose both on nine-under.
"That's the most incredible day I've ever had on the golf course," said a beaming Lowry afterwards. "I honestly can't explain what it was like. The crowd was incredible."
That they were, staying long after Lowry and Holmes, in the final group, had left the 18th green to sing and chant the Irishman's name.
However, Shane played his part, too, producing an inspired performance to put himself on the brink of winning his maiden major. His 197 three-round total also set a new 54-hole record for the Open Championship, beating the previous mark - set by Tom Lehman in 1996 - by one. Lehman, of course, went on to win that year.
Key to his performance? Hitting greens. Lowry leads the field in GIR.
He is also the 26th player to lead The Open by four or more shots after three rounds since 1990. Of the previous 25, 22 have gone on to win.
History is on his but side but he's refusing to get preoccupied with such details. The job, he insists, is only three-quarters done.
"I know tomorrow is going to be a difficult day. I know there's some bad weather coming in. But, look, I'm in a good position and I just have to do what I've been doing all year and hit the reset button tonight and go out there and shoot as good a score as I can tomorrow. And hopefully that's good enough tomorrow evening."
Hoping to spoil what promises to be the mother of all parties is Ryder Cup hero Fleetwood, who goes off with Lowry in the final group at the weather-rescheduled earlier time of 1.47pm.
He's ready for the fight.
"I'm very, very happy to have that challenge," said the
Englishman. "If you had said at the start of today, at the start of the
week, at the start of the year, you're going into the last round,
whether I'm four back, five back, it doesn't matter, I'm in the last
group Sunday at The Open and playing with Shane, and the majority of the
crowd might not be with you, I would have said, 'Yeah, that's fine'.
"I'm looking forward to it, to be honest with you. It's going to be another chapter in my career, no matter what happens. And it's going to be a very special day."
How special a night it proves to be for those on this island looks likely to depend on Fleetwood.
Ireland will waken with a huge collective hangover on Monday morning.
Whether that's from celebrating or sorrow-drowning, we'll know very soon.