It seems the United States Golf Association is not out to torture the field at the US Open after all.

With no players under par after 36 holes, the USGA chose to water the greens at Oakmont on Friday night and this morning.

The greens on the second, third, fifth, sixth and 13th - the firmest on the course - were watered again early Saturday morning.

The USGA now feels they will be no firmer at any point in the third round than they were late in the day on Friday.

Only four players have carded sub-par rounds this week, two on each day.

Paul Casey shot a 66 yesterday, an achievement so outstanding that players stopped putting on the practice green adjacent to the ninth hole to applaud him when he finished.

Even the world's best player was looking for help, Tiger Woods calling for the greens to be watered as soon as he finished his second round on Friday, a 74 which included six bogeys.

"It's close. It's right on the edge," he said when asked if the course was getting away from the USGA. "If they don't water the golf course it's going to be a lot more difficult."

But what the USGA giveth, the USGA taketh away.

The par-three eighth is again playing again from the back tee and will be 279 yards today. The 10th is also playing from the back at 462 yards.

The par-five 12th, which has played up to 667 yards this week, will be moved up to 632 yards on Saturday to bring a different landing area into play, one that slopes from left to right.

There was no sign of an early improvement in the scoring however. Masters champion Zach Johnson was four over after six holes and 14 over.

Kiwi Michael Campbell, the 2005 champion, was three over after four holes and 13 over.

Graeme McDowell is tied 13th on five over par, five behind overnight leader Angel Cabrera from Argentina.