Reigning champion Rory McIlroy has insisted that June's US Open will prove a much more difficult test than last year.
The Northern Irishman claimed his first Major win at the same event nearly 12 months ago, breaking a host of records at the Congressional course in Maryland.
McIlroy was victor by eight shots and took four strokes off the champion record with his score of 16-under-par, but he expects a much sterner test at the Olympic Club in San Francisco.
"The thing that made the scoring low was the fact they got so much rain before," said McIlroy.
"Last year was a bit of an exception. I'm expecting something around level par isn't going to be too far away."
McIlroy lost his world number one spot to Luke Donald on Sunday following the Englishman's top-seven finish at Zurich Classic.
