Rory McIlroy's Honda Classic walk out after Nike switch sparks concern

Applause drowned out the pulsating music on Tuesday as Rory McIlroy made his way to the X taped to the carpet in the resort ballroom. McIlroy, wearing jeans, a dress shirt and pointy-toed shoes, had just been introduced as the first global brand ambassador for Bose, an audio equipment company.

It was a timely merger of man and machine. If anybody needed noise-cancelling headphones to tune out the world, it was McIlroy, whose slow start in 2013 has generated criticism on both sides of the Atlantic.

On Friday he set more tongues lashing by abruptly withdrawing from the Honda Classic after completing eight holes of his second round. It was the first time in 55 starts as a professional on the PGA Tour that he withdrew during a tournament.

McIlroy returned this week to PGA National Resort and Spa seeking to become the 41-year-old tournament's only back-to-back champion besides Jack Nicklaus. Instead, the event led to his latest disappointment since the 23-year-old Northern Irishman made the highly lucrative but risky move of changing his equipment from Titleist to Nike at the beginning of the year.

The early returns have not been promising: he missed the cut in Abu Dhabi in his season debut, switching to his old putter in the second round, and lost in the first round last week in a World Golf Championships match-play event outside Tucson.

The week of his title defence began with McIlroy brushing off criticism in the news media in the United States and the United Kingdom over his equipment change. "It's not like I'm pushing for answers or I'm looking for answers," he said. "Everything's there. It's just a matter of putting it all together."

Asked if reporters were making too much of it, he laughed and said: "Of course. Like you always do with everything."

McIlroy was not laughing when he walked off the course after depositing his second shot on his ninth hole, the par-5 18th, into the water. It was his third wet ball of the day, and he stood at seven-over after eight holes.

Before driving away from the PGA National course, McIlroy told reporters: "I'm not in a great place mentally. I can't really say much, guys. I'm just in a bad place mentally."

Ernie Els and Mark Wilson, who were paired with McIlroy, were unaware of any physical distress that would have prompted him to retire from the tournament. McIlroy gave no hint of a problem before his round, posting on his Twitter account a photograph of a birthday dinner for his mother, Rosie.

An hour after his withdrawal, in a statement released by his managers, McIlroy said he was bothered by a sore wisdom tooth that did not respond to a pain reliever.

"It was very painful again this morning, and I was simply unable to concentrate," he said.

McIlroy added, "This is one of my favourite tournaments of the year and I regret having to make the decision to withdraw, but it was one I had to make."

Walking off the course in the middle of a round is rare, but Tiger Woods has done it twice in the last two years, most recently during a dismal final round at the 2012 Doral tournament when an Achilles tendon injury flared.

"I'm a great fan of Rory's, but I don't think that was the right thing to do," said Els, a four-time major winner and the 2008 Honda Classic champion. "Hey, listen, if something was bothering him, it was bothering him, and all credit to him for trying to play through whatever pain he was in. He obviously couldn't do it after nine holes anymore. Toothache, it's not fun, I guess."

Woods, who has endured his share of controversy and media scrutiny, said McIlroy should choose his words more carefully.

"He's just got to be more - just got to think about it a little bit more before you say something or do something," said Woods, who shot a second consecutive even-par 70. "It can get out of hand, especially when you get into social media and start tweeting and all those different things that can go wrong."

Additional Reporting Reuters