All of the pre-championship fears that the unique challenge of Chambers Bay, with its vast elevation changes, might just be too much for the field, were utterly dispelled in yesterday's first round, in which we had some very 'un-US Open-like' scoring.

There were five-under-par 65s from Dustin Johnson and Henrik Stenson, which were posted early in the day and ended up being the best of the round.

But Stenson and Johnson, both ranked in the World's Top 10, have plenty of near pursuers, with 23 other players carding scores in the 60s. The closest of them is Patrick Reed, who shot a four-under-par 66.

There were also some first-round shockers at the links-style course.

An 81 for recently crowned Players' champion Rickie Fowler, and a career worst US Open round of 80 for Fowler's playing partner Tiger Woods - though that's less of a shock these days.

The Irish challenge is led by Shane Lowry, who said he loved this course in practice this week, and for a while yesterday he crept into the top 10.

The Offaly man got to two under par entering the back nine and in the end was very happy with a one-under 69.

"I played lovely," he told RTÉ Sport. "Being brutally honest, I'm still not that comfortable on the greens but off the tee and my iron play was pretty good.

"There was one pretty average iron shot but the rest was pretty good.

"I'm looking forward to the next few days now. Hopefully the course will be a little bit softer in the morning and we can hit a bit closer.

"It's quite hard to get the distance controlled right out there."

For world number one Rory McIlroy it was a tale of short missed putts on the back nine in a two-over-par 72 but, on the credit side of things, his ball striking looked back to form.

Graham McDowell struggled from his double bogey on the first hole and shot a 74 while Darren Clarke posted a 77.

Irish Tee Times - US Open Day 2

3.55pm: (7.55am local) - Lee Janzen, Ollie Schniederjans, Darren Clarke 
4.39pm: Shane Lowry, Ben Martin, Stephen Gallacher  
10.06pm: Hideki Matsuyama, Graeme McDowell, Matt Kuchar
10.28pm: Martin Kaymer, Gunn Yang, Rory McIlroy