Oakmont - The world's best golfers on Tuesday were preparing for the ultimate US Open test at Oakmont with a mixture of excitement and trepidation.
The course is not an untamed monster like Chambers Bay in Washington State last year, but its distinctive bunkers are forbidding and its greens are among the fastest and must undulating on the circuit.
On top of that, the eighth hole is the longest par-three in US Open history at 300 yards, the 12th at 667 yards the second-longest ever par five and the closing hole is an unforgiving 484-yard par four many consider to be the hardest on the Open rotation.
The par is at 70 and few think that will be bettered by Sunday evening. The last time the tournament was held at Oakmont, in 2007, Angel Cabrera won at five-over.
Asked if he felt trepidation or excitement with two days to go until Thursday's start, Rory McIlroy, who won the US Open in 2011 at 16-under par said: "Trepidation, I guess.
"Yeah, excitement is a good way to describe Augusta (Masters), but it really depends the venue that you play a US Open at as well.
"But, yeah, this week it's definitely not excitement. I mean, it's definitely not that."
"You know you're going to be put under a lot of pressure on basically every single golf shot you hit out there.
"So you have to be prepared for that. You have to be prepared for how mentally demanding it's going to be, how much concentration you're going to need out there."
The four-time major winner from Northern Ireland is not alone in feeling his stress levels on the rise.
World number one Jason Day, who forms with McIlroy and defending champion Jordan Spieth what is being regarded as golf's new "Big Three", said that he, too, was unsure what the week would hold in store for him.
"I've never been more stressed in my life than right now," said the reigning PGA champion, who is also battling a bad cold.
"Sometimes your immune system gets a little heated, and you're more susceptible to getting some illnesses that way," he said.
"It doesn't help that my father-in-law was sick during the Memorial, so that kind of passed it along to me.
"I'm not trying to make any excuses this week," he added. "I'm going to be ready for the start Thursday."
Day, Spieth and McIlroy, the top three in the world rankings, have all joined the list of major winners, which cannot be said of Rickie Fowler, another leading member of the new wave of players.
CRAZY AND PENAL
Fowler said Oakmont had "the craziest greens I've ever played and most penal fairway bunkers I've entered," before adding "It's a fair golf course."
The Californian believes he has a real chance to finally break his major duck.
"I think there's a bit of a gap right now. I've got a little way to go. And, yeah, they've won majors. So I've got some catching up to do.
Other potential storylines surround Spieth's mindset in the first major since his Masters final round meltdown in April, Dustin Johnson's quest for a first major title after his disastrous three-putt at the 18th hole of last year's US Open and whether the fast-improving Hideki Matsuyama can become the first player from Japan to win a Grand Slam tournament.
But the biggest galleries, in the continued absence of the injured Tiger Woods, will likely be following Phil Mickelson as he bids, for the third straight year, to become just the sixth player to win all four major titles, having finished runner-up a record six times.
Mickelson, who turns 46 on Thursday, would also be the oldest player ever to win the US Open.