The first tee-shot was struck just over an hour and a half ago by sectional qualifier Danny McCarthy, starting from the 10th, alongside fellow American Andres Gonzales.

Gonzales is the early leader and is two under through his first six holes, one clear of amateur Scottie Scheffler, Andrew Landry, Kevin Streelman and Frenchman Romain Wattel.

Have a look at the full leaderboard here., external

Image source, AP

Whatever happens between now and Sunday (and Monday if it goes to a play-off), we can be sure the Oakmont course will be a huge part of the storyline.

Reputed to be the toughest course in the USA, it has hosted 11 majors and its winners have collected 57 majors between them. 

Argentina's Angel Cabrera triumphed the last time it hosted the US Open in 2007, while Ernie Els overcame Colin Montgomerie and Loren Roberts in a play-off in 1994.

Image source, AP

Image source, Getty Images

There's no easing yourself in today - we've got plenty of big names out early.

World number three Rory McIlroy and Masters champion Danny Willett tee off together in five minutes at 13:24 BST alongside American Rickie Fowler.

Defending champion Jordan Spieth, Zach Johnson, and US Amateur winner Bryson DeChambeau start at 13:35 BST.

American Phil Mickelson, 2013 winner Justin Rose, and Sweden's Henrik Stenson are one of the final groupings, going at 19:09 BST.

They are followed by world number one Jason Day, fellow Australian Adam Scott and South Africa's Louis Oosthuizen at 19:20 BST.

Peruse all the tee-times here.

Image source, AP

A test of patience, a test of endurance and rough so long you could lose a child within it ... welcome to the US Open, the most brutal and unforgiving of all the majors.

Four days of compelling golf awaits...