McIlroy, admitted to being "mentally flat" on Thursday as he began his  reign as the World No 1 at the WGC-Cadillac Championship with a  disappointing 1-over 73. 
                                
Rory McIlroy had a frustrating first day 								     
 
On a difficult windy day on a Doral Resort's Blue Monster course  featuring one of its most punitive roughs in years, McIloy was in good  company, the 22-year-old Northern Irishman finishing the day just a shot  behind Tiger 
Woods, Phil Mickelson and YE Yang and in a nine-way tie  that included World No 4 Martin Kaymer and the highly-ranked young  Australian Jason Day, but it was less than he had hoped for 
"All of a sudden you're there (top of the rankings) and you're  like 'Well, what do you do?' I just need to go out and set myself a  target tomorrow," McIlroy told the media afterwards. 
He is seven behind Cadillac Championship pacesetters Adam Scott  and Jason Dufner and perhaps his one big crumb of comfort was that Lee  Westwood, who, like Luke Donald (70), could take back the number one  spot with a victory here on Sunday, handed in a 76. 
While McIlroy was winning the Honda Classic on Sunday, Westwood  was charging into fourth place with his best-ever round in America - a 
63 - but this time the 38-year-old bogeyed his first three holes and finished down in the nether region of the 74-strong field. 
Australian Scott, already with a WGC title to his name, and  American Dufner, runner-up at the USPGA Championship last August, led by  two from Dane Thomas Bjorn and Masters champion Charl Schwartzel, while  the leading British player was Justin Rose after a 69 - one better than  Donald and Scot Paul Lawrie. 
"I was mentally flat and it was a bit of a struggle. It was a  pretty tricky day, but obviously there was good scores out there. I just  didn't really get anything going," McIlroy said as he tried to find a  reason for his sluggish start. 
"After what happened last Sunday - Tiger shoots 62, I end up  winning to go to world number one - obviously people are going to talk,  but I think everyone has to remember that there's 80 other players in  this field or whatever it is and it's not just about a couple of guys." 
McIlroy's see-saw day was established early. He missed the green  at the 11th, his second, and bogeyed the hole, but came back with an  11-foot birdie putt on the next. 
He almost found the water off the tee at the demanding 18th -  Darren Clarke and Sergio Garcia both put two balls in and had triple  bogeys there - and dropped another shot, but then almost matched Woods'  eagle on the long first. 
Then came two bogeys in a row, however, and it could have been  worse. His approach to the third hit the rocks beside the water, but  bounced left and back on to the grass. 
Woods, in the meantime, began as he finished last week with an  eagle - it needed only a two-foot putt on the downwind par five first -  but that was good as it got. 
He birdied two more of the par fives, but had four bogeys.
 
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