Keegan Bradley has admitted that he can't afford to play attacking golf over the weekend at the US Open as he looks to close the gap on leader Martin Kaymer.

The American is among a group of players eight shots behind Kaymer, with whom he played in the first two rounds, but he is certain that the Pinehurst course is not forgiving enough to encourage a change of tactics.

"The course is too hard. You just got to stick with the game plan. There's no place to force anything. It's just similar to Augusta in that there's a double on every hole if you're not careful, so stick to the game plan," Bradley told members of the media.

"We've got to see what happens tomorrow, but the back nine on Sunday is where it all kind of happens. Steady golf out here is going to be tough.

"You need to go out there tomorrow, make a bunch of pars and you never know what's going to happen."

Bradley is looking for his first win since the 2012 Bridgestone Invitational.