World No.1 Adam Scott sits nine shots off the lead early in the third round of the US Open Championship at Pinehurst No.2 as leader Martin Kaymer shows some cracks in his game.

In extremely hot and dry conditions and with officials enforcing a very tough setup, Scott is one over par on his round through nine holes to fall to one over for the championship, currently tied 12th.

While he started 10 shots adrift of the lead Scott has gained a little ground as the previously near-flawless Kaymer bogeyed two of his first four holes to fall back to eight under par.

The German, who opened with back-to-back five-under 65s, now leads by five over Americans Kevin Na and Brandt Snedeker.

Scott opened his round by making two impressive par-saving putts from 10-feet and was also clutch getting up and down on the third and fourth holes.

The Queenslander then pumped a drive down the par-five fifth and hit a beautiful six iron to seven-feet with his second.

But his eagle putt lipped out forcing him to settle for a birdie.

The 33 year old was looking to start a run but his tee shot on the par-three sixth failed to clear the false front of the green and, although his chip settled around six feet from the hole, he missed the putt to give the gained shot right back.

He carded another bogey on the par-three ninth when he failed to get up and down from the sand.

Jason Day is two over on the day through 12 holes to be three over in a tie for 19th and Aaron Baddeley is four over on his round through 13 holes to sit at five over in a tie for 30th.