The Olympic Club's layout had already taken its toll on many with only three players from that morning group under par as the opening session of play drew to a close.
29 year old Michael Thompson, a former runner-up at the US Amateur and low amateur in this event at Torrey Pines in 2008, was the standout however, a birdie at his final hole completing a round of 66 to give him a three shot lead as he walked from the 18th green.
Thompson began with a bogey today but five birdies in eight holes between the 7th and 14th holes today set up the round. The birdie from 8 feet at the last was icing on the cake to a large extent but either way it was an impressive start to what was his second US Open.
Thompson, a member of the PGA Tour over the last two years, leads by three over Tiger Woods and David Toms with the golf course catching up with several others who were under par early.
"This is one of my favourite golf courses," said Thompson. " So I've got good feelings coming in here. I just got the putter hot today."
Thompson indicated that coming early to the event was important for his preparation. "Well I was fortunate enough that I was able to come out on Friday. So I got to prepare on site. And that was really big to be able to spend three full days really with nobody out here, I had the chipping green, putting green, all to myself. I really got some good practice."
"Because, come tournament time, all the practice facilities are really, really hectic. A lot of, we like to, I like to describe it all as like a big cocktail party. Just a lot of people and it's hard to get good work done.
Woods was particularly impressive, hardly missing a shot and producing some high quality shots during his round of 69. Not only was his score impressive but the quality of his play and his mere presence will remind everyone that he is close to his best once again.
"I played well today, said Woods. "I felt like I had control of my game all day and just stuck to my game plan and executed my game plan."
"I made a couple of changes out there because the wind had shifted and the fairways were faster and so it was, we knew it was going to get quick as the week progressed, but we didn't think it was going to happen overnight.
"We teed off the same time yesterday and it wasn't that bad. Come out here today and it's just like they used sub air on the whole place and it was just quick. And we had to make the adjustments and I felt like I did that today."
Kevin Na and Brendan Grace were amongst the early leaders when, playing together, they both reached 3 under early in their rounds only to finish with rounds of 74 and 71 respectively.
Alistair Presnell is the surprise packet amongst the Australians, leading the nine strong contingent after an impressive debut in the event.
Presnell played in the latter part of the morning field and despite a bogey at the first was rock slid throughout. Birdies at the reachable par four 7th and the dangerous par three 13th took him under par for the tournament and into a share of second position with Woods and Toms at the time. A bogey at the long par five 16th saw him at even par and two pars to finish will have him very well positioned heading into day two.