There was no one up against Dustin Johnson when he walked to the 18th green of the U. S. Open at Chambers Bay on Sunday, just himself, his putter and his past golfing demons. After hitting two brilliant shots on the par-5, the seventh-ranked golfer in the world had a 12-foot putt for his first major win, then four feet for a tie and missed both putts. It was a choke, plain and simple.