
The 2012 US Open champion had played his first 15 holes of the par 70 at Oak Hill in a magnificent seven-under par and knew that he could become the first man in the history of major championships to break 63.
However, a pushed tee-shot at the seventh, his 16th, led to a bogey and two closing pars meant the American Ryder Cup star had to 'settle' for a course record 64.
"I was thinking about it, once I birdied six, I was thinking about the all-time major record, and I was about 99 percent sure it was 63."Webb Simpson
Simpson said: "I was thinking about it, once I birdied six, I was thinking about the all-time major record, and I was about 99 percent sure it was 63.
"It's so hard, because on one hand, you want to go for it. You want go for the record. But you can't do that on a golf course this hard and I wasn't doing that at any point today. I was trying to be patient and trying to be conservative."
The Oak Hill course record of 64 had first been set by the great Ben Hogan in 1942 and has not been broken since.
Simpson said: "It's pretty special. I had no idea what the course record was. But you know, any time you can put your name near Ben Hogan, it's a great thing. So it will go down as one of my most special rounds ever.

"I don't think not tying the major record takes away from the fact that I was able to tie this course record. It was just fun; fun to experience something like that."
Simpson had slumped to five-over during round one but will go into the weekend nicely placed on four-under.
He said: "At five over through eight holes it was a pretty low moment for me. But I kind of had a pep talk with myself on the seventh green, and you know, just told myself, one hole at a time and tried to get a birdie here, a birdie there, and somehow played the last ten or 11 holes under par.
"I was able to do that, and I birdied 18 yesterday, which was huge for my confidence. Two over felt like 64 yesterday after being five over."

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