Keep calm, it's the US Open
 Darin Bevard using a stimpmeter on the ninth green during a practice round for the 2016 U.S. Open at Oakmont Country Club in Oakmont, Pa. on Wednesday, June 15, 2016. (Copyright USGA/Joel Kowsky)

Darin Bevard using a stimpmeter on the ninth green during a practice round for the 2016 U.S. Open at Oakmont Country Club in Oakmont, Pa. on Wednesday, June 15, 2016. (Copyright USGA/Joel Kowsky)

It was said many years ago but the hellish pronouncement of the founder and designer Henry Clay Fownes should be posted on a large sign at the entrance to Oakmont Country Club.

“Let the clumsy, the spineless, the alibi artist stand aside!” he said.

Shane Lowry said it his way.

“No bluffers are winning this week.”

Rory McIlroy, the 2011 champion, was equally emphatic. 

“It's going to be quite the mental grind.”

Fownes’ philosophy is music to the ears of the USGA, whose president, Diana Murphy yesterday reminded everyone exactly what the US Open is all about and why it is not just another run of the mill PGA Tour event.

The US Open is intended to be, she said, “the ultimate test of golf.”

No course has hosted the US Open as many times as Oakmont. And while there has been some muttering about the depth of the rough for this ninth staging, nobody has seriously complained. Oakmont, a legendary venue, does exactly what it says on the tin.

Fownes’ belief that “a shot poorly played should be a shot irrevocably lost,” has been taken to its ultimate expression on the outskirts of blue collar Pittsburgh, a town that lives for sport.

Yesterday, they were hailing the Pittsburgh Penguins with a parade for their fourth Stanley Cup win. On Sunday, many of the fans who were at the Consol Energy Center rink to hail the 2016 ice hockey champions will head out to see the players skate around the greens at Oakmont.

They are so fast that the fact that Edward S. Stimpson, Sr. was inspired to invent the Stimpmeter having witnessed Gene Sarazen putt off a green at Oakmont during the 1935 US Open says it all.

With many of them running steeply from front to back and with green speeds of 14 (at least) making them faster than any other course in the world, the test is a mental as much as a physical one.

 Rory McIlroy hits his second shot on the 18th hole during a practice round for the 2016 U.S. Open at Oakmont Country Club in Oakmont, Pa. on Tuesday, June 14, 2016. (Copyright USGA/JD Cuban)

Rory McIlroy hits his second shot on the 18th hole during a practice round for the 2016 U.S. Open at Oakmont Country Club in Oakmont, Pa. on Tuesday, June 14, 2016. (Copyright USGA/JD Cuban)

Lee Trevino, who said Oakmont was the only course where you could play a US Open at a day’s notice, claimed every time he two-putted at Oakmont he knew he was passing somebody on the leader board.

Given the severity of the test — super-fast greens protected by four and a half inch rough so thick it’s impossible to walk through if you drag your feet even a little — many of the world’s best players are certain to contend.

Given his US Open record over the past five years (2nd, T59, T2, T4 and T9) and his status as world No 1, Jason Day is the bookies’ favourite at 7/1 ahead of McIlroy (15/2) with defending champion Jordan Spieth at 16/1.

Day didn’t play in 2007, when Angel Cabrera won his first major. But given the leaderboard that day — the Argentinian was followed home by Jim Furyk, Tiger Woods, Niclas Fasth, David Toms and Bubba Watson with Paul Casey and Justin Rose in the top 10 — there is no archetypal US Open winner at Oakmont other than the fact that they have all been great players.

Many will wonder if Phil Mickelson, putting better than anyone in the US bar Jason Day and Steve Stricker, can finally complete the career grand slam after six runner up finishes.

But there are many other storylines. Can Dustin Johnson shake off last year’s 72nd hole three-putt and the feeling that he’s simply a major accident waiting to happen after two seconds and five 11 top 10s in the last 26 majors?

Can Spieth win a third major and put the Masters disaster behind him for many, even if he did win again just a few weeks ago? 

Is it finally Rickie Fowler’s time to shine or will Branden Grace or Louis Oosthuizen become the first South African to win the title since Retief Goosen in 2004?

Irish fans will wonder if McIlroy can win a US Open on a hard and fast course that will require as much patience and discipline as putting and chipping prowess.

Given what we saw in the Masters, it’s still difficult to truly believe he can be that player. But he’s playing with such confidence from tee to green that if he retains the touch on the greens he showed when posting career-best putting numbers in the Memorial two weeks ago, a fifth major is a real possibility.

The 27-year old from Holywood spoke in the build up about hitting just two drivers, about discipline, about a game plan and about aggression at the right time.

On paper, at least, he ticks all the boxes at a venue that has produced a list of US Open champions in the thoroughbred class with Ben Hogan (1953), Jack Nicklaus (1962), Johnny Miller (1973), Ernie Els (1994) and Angel Cabrera (2007) all winning here.

 General view of the clubhouse on the 18th hole during a practice round for the 2016 U.S. Open at Oakmont Country Club in Oakmont, Pa. on Monday, June 13, 2016. (Copyright USGA/Joel Kowsky)

General view of the clubhouse on the 18th hole during a practice round for the 2016 U.S. Open at Oakmont Country Club in Oakmont, Pa. on Monday, June 13, 2016. (Copyright USGA/Joel Kowsky)

Two of the Argentinian’s three wins in the US are majors and while he said yesterday that hitting fairways, followed closely by having the luck to hole a few long putts were two big keys to winning at Oakmont, the most important ingredient is mental strength.

While Graeme McDowell has it in spades, it’s an element of the game that has sometimes eluded both McIlroy and Lowry when the going is especially tough on the nerves.

“Mentally, that's what's going to win it for you this week. It's how people can keep their calm and keep their composure,” McIlroy said.

Lowry has had such a tough year on the greens that he may need a good putting week to have any chance.

The good news is that he feels good about that aspect of his game, explaining: “I have a nice feeling about my putter this week  it's about committing to hitting good putts.”

What’s going to be more important is acceptance of bad breaks.

“We know we are going to get bad breaks, we know we are going to get bad lies, we’re definitely going to make bogeys and probably odd double,” he said. “That’s just the way this course is. 

“It is one of those weeks where will be a lot of broken men leaving here on Sunday evening and on Friday evening as well.”