Former world No.1 Jason Day has delivered a brutal reality check for club golfers as he sets his sights on becoming the first Australian to win a US Open at famed Oakmont Country Club.

Built in 1903 with the express purpose of being the toughest golf course in the world, Oakmont has undergone a recent renovation under the guidance of Gil Hanse and promises to be as torturous as it has ever been.

Rough brushing players’ calves and sloping greens nudging 15 on the Stimpmeter have many questioning whether the best players on the planet will break par for 72 holes.

Wearing shorts emblazoned with the American flag that caused a social media stir of their own, Day said in a video posted to DP World Tour social media channels that not only would an 18-handicapper not play to their handicap, they’d need more than triple that number to even come close.

“A legit 18 marker, I think 150 is pretty solid,” said Day, which averages out to more than eight shots on every single hole.

“They would just struggle.

“I mean, it’s difficult out there. Most 18-handicappers typically don’t have the greatest control off the tee box. They’re probably hitting this swipey cut into the right rough. They’ve got no knowledge of how to hit the angle of attack on some of these so they’re hitting these shots which are coming out way left.

“They’re going to be beaming the ball across, back and forth.

“150 I feel like is very good for an 18-marker.”

Day played a practice round with fellow Australian Min Woo Lee on Tuesday, who also said that players who average 90 in their club competitions have no chance of breaking 100 at Oakmont at its fiercest.

“120,” was Lee’s estimation, 30-over an 18-marker’s handicap.

“The greens are so slick and slopey. And the rough is … I mean, we can barely get it out of the rough, so I don’t think an 18 handicapper would be able to get out of the rough.

“I don’t know if that’s ridiculous or generous, I’m not sure.

“Hopefully someone can experiment and average it out for us. But it’s a lot.”

Lee and Day make up a third of the Aussie contingent at Oakmont while there are 10 Australians teeing it up at the LPGA Tour’s Meijer LPGA Classic for Simply Give.

A week out from the KPMG Women’s PGA Championship, major winners Minjee Lee and Hannah Green will head the charge as Kirsten Rudgeley, Kelsey Bennett, Maddison Hinson-Tolchard and Amy Walsh line up for the Hulencourt Women’s Open in Belgium.

US Open Oakmont Country Club, Oakmont, Pennsylvania 9:18pm* Adam Scott 10:02pm Cam Davis 10:02pm* Cameron Smith 2:41am Ryan Fox (NZ) 3:03am Min Woo Lee 3:36am Jason Day 3:58am* Marc Leishman

Recent champion: Bryson DeChambeau Past Aussie winners: David Graham (1981), Geoff Ogilvy (2006) Prize money: $US21.5m TV times: Live 8:30pm-10am Thursday, Friday; Live 12am-10am Sunday; Live 1am-9am Monday on Fox Sports 503 and Kayo.

LPGA Tour Meijer LPGA Classic for Simply Give Blythefield Country Club, Belmont, Michigan 9:15pm Sarah Kemp 9:15pm* Fiona Xu (NZ) 9:48pm Cassie Porter 9:48pm* Hannah Green 10:10pm Robyn Choi 10:10pm* Minjee Lee 11:05pm* Karis Davidson 11:16pm Grace Kim 3:10am* Stephanie Kyriacou 3:54am* Gabriela Ruffels 4:05am Hira Naveed

Recent champion: Lilia Vu Past Aussie winners: Nil Prize money: $US3m TV times: Live 5am-8am Friday on Fox Sports 507; Live 5am-8am Saturday; Live 6:30am-8am Sunday; 9am-11am Monday on Fox Sports 505 and Kayo.

Ladies European Tour Hulencourt Women’s Open Hulencourt, Belgium 4:43pm* Kelsey Bennett 4:54pm* Kirsten Rudgeley 5:16pm* Momoka Kobori (NZ) 5:38pm Amy Walsh 9:17pm Amelia Garvey (NZ) 10:01pm Maddison Hinson-Tolchard 10:23pm* Wenyung Keh (NZ)

Recent champion: Patricia Isabel Schmidt Past Aussie winners: Karen Lunn (1988, 1990), Corinne Dibnah (1991) Prize money: €300,000 TV times: Live 11:30pm-2:30am Thursday, Friday on Fox Sports 507; Live 9pm-11:30pm Saturday; Live 9:45pm-12am Sunday on Fox Sports 505 and Kayo.

Japan Golf Tour/Korean PGA Tour Hana Bank Invitational The Heaven Country Club, South Korea 8:01pm Brad Kennedy 9:40pm* Junseok Lee, Michael Hendry (NZ)

Recent champion: Takashi Ogiso Past Aussie winners: Junseok Lee (2022) Prize money: KRW1.3b

Epson Tour Great Lakes Championship The Highlands, The Heather, Harbor Springs, Michigan Australians in the field: Su Oh, Jess Whitting

Recent champion: Inaugural event Past Aussie winners: Nil Prize money: $US250,000

HotelPlanner Tour Raiffeisenbank Golf Challenge Kaskáda Golf Resort, Brno, Czech Republic 9:30pm Hayden Hopewell 9:30pm* Sam Jones (NZ) 9:40pm* Jye Pickin

Recent champion: Hamish Brown Past Aussie winners: Nil Prize money: €300,000

LET Access Series Amundi Czech Ladies Challenge Panorama Golf Resort, Kacov, Czech Republic Australians in the field: Stephanie Bunque, Justice Bosio, Belinda Ji, Abbie Teasdale, Kristalle Blum

Recent champion: Helen Briem Past Aussie winners: Nil Prize money: €45,000

Legends Tour Costa Navarino Legends Tour Trophy Costa Navarino, Greece 5:17pm Michael Campbell (NZ) 5:28pm Scott Hend 6:23pm Michael Long (NZ)

Recent champion: Clark Dennis Past Aussie winners: Nil