Adam Scott sits six shots off the pace at the halfway mark of the US Open at one-over but remains defiantly committed to his goal of even par.

The 2013 Masters champion is convinced Chambers Bay will bare its teeth over the weekend, expecting the United States Golf Association (USGA) to increase the difficulty of the set up and bring the leaders back to the pack.

Patrick Reed and current Masters champion Jordan Spieth lead the pack at five-under and while Reed believes he needs to go deeper on the weekend, the young Americans expect things to toughen up.

“I start tomorrow optimistic that if I find a birdie early, I’m back to level par and right on my mark again,” Scott said after a clutch nine-foot par save on the last.

“Now they’ve got 156 guys through they can toughen this course up and I suspect we’ll see firmer greens tomorrow.”

A large percentage of players are already bemoaning the state of and difficulty of the course as they struggle on the bumpy fescue greens.

“It’s borderline laughable on some of the greens and some of the pin positions, when we’re actually almost better off plugged in a bunker than being on the top of a ridge, like on the fourth,” Swede Henrik Stenson said.

“And it’s pretty much like putting on broccoli.”

Of the 20 players above Scott on the leaderboard, only Spieth and Jason Dufner (even par) have a major in their back pocket, something that could come in handy as pressure mounts.

“Generally, I think knowing you can do it is a very good thing,” Scott said.

“Tomorrow is a great day for me to just do my stuff again and then I’ll have the first nine on Sunday to hopefully put myself in a position where you can really lean on it and know you can get it done.

“I’ve got 27 holes to keep it together, to then be able to use it to my advantage.”