Rory McIlroy’s nightmare start to 2013 has gone from bad to worse after he was dumped out of the world match play championships by close friend Shane Lowry.

Major winner McIlroy was beaten on the 18th green by the young Offaly man in their first round clash at the snow delayed event in Arizona.

Lowry, whose father Brendan won an All-Ireland football medal with Offaly, survived a nervy start to beat his long time amateur international team partner in the shock of the tournament.

World number one McIlroy was joined at the exit by Tiger Woods, beaten 2&1 by fellow American Charles Howell.

The latest blow comes as questions remain over McIlroy’s decision to switch clubs to Nike in a $250million deal at the end of last season.

The 23-year-old began his new deal when he missed the halfway cut in Abu Dhabi last month and it didn’t get any better in Arizona ahead of his defence of the Honda Classic in Florida next week.

McIlroy admitted: “I drove really well, but couldn’t take advantage of that. If I’d hit my irons better it could have been a different story.

“I could have been three or four up early on, but let him get back into the match and he had a nice little run.”

A surprised Lowry, who chipped in twice on the back nine, said: “My knees were knocking over that final three-foot putt on the 18th green.

“I was very nervous going out and quite mad at myself for that, but I had a bit of luck that I needed and said to my caddie that he’s not going to be liking this at all.”

Shane Lowry shakes off Rory McIlroy's handGoogle Images