Vijay Singh produced one of the greatest back nines in golfing history on Friday.
Tom Watson, who had a share of the lead after the first round, had warned earlier in the day that the course was there for the taking - and they proved prophetic words.
With the greens soft and receptive, Singh took full advantage of the conditions to race to the top of the leaderboard with Jim Furyk.
To me it is no surprise that it was Singh who made the most of conditions.
He has already won two tournaments this year and is the genuine form horse at this year's tournament.
He also has previous Major success at the US Masters and the USPGA.
The one dark spot in his round on Friday came when a heckler in the stands at the 14th brought up the Fijian's objections to Annika Sorenstam's participation in a men's event.
Singh said he did not notice - and the heckler was quickly ejected.
My colleague John Murray was lucky enough to be in the galleries who followed Tom Watson in his scintillating round on Thursday.
He made the observation that it was mostly made up of, shall we say, the senior citizens of the golfing public.
They will be thrilled to bits that one of the great heroes of this game is once again figuring on a major championship leaderboard.
I suspect he will fade away to become a fond memory of this US Open.
He managed a 72 today, leaving him tied for 10th, but that is nonetheless a fantastic effort at the age of 53.
I think the current stars of the game will dictate the course of the US Open now - notably Singh, Jim Furyk, who has emerged has one of the best players not to have won a Major, and of course defending champion Tiger Woods.
I have been impressed with Tiger's mental strategy so far.
He was not swinging well in his first round on Thursday but his course management ensured that the technical flaws did not derail his challenge.
Woods has ironed out the flaws in his swing
He corrected a couple of problems after that first round and that enabled him to commit to his swing in the second.
It came as no surprise that it translated to such an effective scoring round.
Woods is now three shots off the pace and the records show that he has never won a Major from so far behind.
That means the third round is crucial to his chances, but the signs are good if he can back up Friday's 66.
Colin Montgomerie was clearly frustrated in the extreme by his second-round 74 and he declined the media's invitations to share his thoughts.
No surprise there.
But the one message he sent to the waiting reporters was that he was pleased to have made the cut - something he failed to do in his last three tournaments.
Britons who can feel a little more pleased with their performances include Justin Rose who is here for the weekend at one over and Brian Davis, who having qualified has ensured he will play all four rounds at three over.