Rory McIlroy haunted by sinking feeling ahead of his US Open defence this week The fact that he held the lead at all represented progress, but it would be a stretch to argue that he is even approaching the level that yielded his eight-shot victory at Congressional 12 months ago. Instead, McIlroy heads to the Olympic Club in San Francisco harbouring doubts. Despite six-hour sessions on the range with coach Michael Bannon, whom he has brought to the US from Belfast, he continues to struggle with his driving accuracy - as illustrated by his lapse at the last, where he shut the clubface and pulled the ball at least 20 yards to the left. The 23 year-old also took an average of 31 putts per round in Memphis, far too many if he hopes to become the first man since Curtis Strange, in 1989, to win back-to-back US Opens. Where McIlroy faltered, a resurgent Dustin Johnson flourished on Sunday to seize the title from McIlroy's grasp. Johnson underlined his reputation as an emotional "flat-liner" with a serene 66, including two birdies in his last three holes. In this fascinating duel of the twenty-somethings, it was the jaunty South Carolinian, who secured his sixth PGA Tour win two weeks shy of his 28th birthday. The moment was a significant breakthrough for Johnson, making his second appearance following a back injury sustained in March, when he tried to lift a jet-ski at home in Florida. Already he appears a prime contender for the US Open, breaking the traditional hex whereby no player who prevails the week before ever goes on to win the tournament itself. After all, he played at Olympic Club for the US Amateur as recently as 2007. "I was at home for 10 weeks, so it feels good to get back and compete," Johnson said. I was a little rusty at Memorial, but here I was able to knock some of the rust off. Another running high on adrenalin is Lee Westwood, who made the ideal preparation for his first major success in 57 attempts by winning the Scandinavian Masters in Stockholm by five shots. "I'll tee off with a lot of confidence," said the world No 3, who has changed his irons and putter in readiness for San Francisco. You don't win tournaments by five without playing really well. As if Westwood could want any extra motivation, he has recorded top-three finishes in six of his last 10 majors.