Despite what Nike might like us to believe — surely they learned their lesson with Tiger Woods — Rory McIlroy is not a perfect, infallible being, an icon or an example to small children everywhere. He's a 25-year old golfer who loses his rag now and again — on this occasion he tugged a three-iron shot into a lake and as the red mist of frustration descended, he fired the offending club after it into the murky deep on the Blue Monster's par-five eighth hole at Trump Doral.

He also shot a two under 70, his first first sub-par score from four attempts on the PGA Tour this year, which should assuage the panic merchants for 24 hours. As for Nike, they can look to the fact that McIlroy saw his father beyond the ropes just a few holes after his embarrassing fit fo pique and wondered briefly if he might be in trouble.

Having seen McIlroy put holes in golf bags, and greens, during his amateur career and throw clubs at bags and even bend a short iron out of shape in frustration during the US Open at Merion, Friday's eight hole club-fling certainly won't have surprised Gerry McIlroy.

In fairness to the world No 1, he was contrite, telling Sky: "What happened after the second shot on 8, I wouldn't encourage anyone to do; especially if there's kids watching at home.  First of all, it's expensive and second of all, you shouldn't do it.  But yeah, it was one of those things that heat of the moment, and you know, we'll move on."

He was amusing in his opening exchange with the scribes and eloquent as he tried to explain what's not working in his game.

Q.  What was the distance on 8? 
RORY McILROY:  The second shot or the throw?  (Laughing) must have went a good 60, 70 yards I think.

Q.  Can you laugh at it? 
RORY McILROY:  Felt good at the time. 
Yeah, I mean, look, I just let frustration get the better of me.  It was heat of the moment, and I mean, if it had of been any other club I probably wouldn't have but I didn't need a 3iron for the rest of the round so I thought, why not.  (Laughter).

Q.  Did you actually think of it 
RORY McILROY:  Yeah, there was a split second like should I or shouldn't I, whatever.  But it was  looking back at it, it isn't one of my proudest moments.  But you know, walked away with a bogey and regrouped and did okay from then. 

Q.  Seemed to kickstart you a little bit after that. 
RORY McILROY:  Yeah, it was more, I needed a  yeah, when you're struggling and it's just  you need something to just give you a spark or give you  and I'm not saying that was it, but could of been.  But played a little better on the back nine, but still just not as comfortable with my game as I'd like. So, you know, I've got two more days to try and find something out there and shoot a couple of decent numbers and see where that leaves me at the end of the week.

Q.  Henrik was said he was the first one to come up to you; what did he say?
RORY McILROY:  He said, "Well, if you can't get on SportsCenter with your play, at least you can do it with something else."  He was quite funny.  He's been prone to doing a thing or two like that in the past, as well, so he can relate.

Q.  Do you remember the last time you did it? 
RORY McILROY:  Like that, never.  I've never done it like that.  I've hit the bag.  But I've never went at it that hard. 

As overnight leader JB Holmes followed his opening 62 with a 73 to lead by a stroke from Ryan Moore (71) on nine under par, McIlroy's rollercoaster 70 moved him up 16 places to tied 11th on one under.

Shane Lowry (74) is tied for 23h on one-over with Graeme McDowell (73) a shot further back in joint 29th.

Naturally, following his club-throw, McIlroy was the centre of attention as he once again failed to fire on all cylinders on a day of tough pin positions and firm greens and yet still managed to shoot a good score to go with his opening 73.

After opening with two fine birdies, he started to build up a head of steam when he bogeyed the third (water off the tee) and fourth (three putts) and followed a birdie from 24 feet at the seventh with that poor second shot at the eighth, where he was trying to cut a three iron over the water and back to the centre of the green but ended up pulling it 40 yards left of his intended target.

Re-energised by losing his temper, he improved on the the back nine and made birdies at the par-five 10th (up and down from sand) and 12th (two perfect shots) as well as the 17th  (24 footer) with his only bogey coming at the 14th, where he was bunkered.

"It wasn't the easiest two-under par [70] in the world, but somehow I managed to get it around," McIlroy said. "Just don't feel 100 percent comfortable with my game. I'm just not quite there. 

"The plane of the swing coming down just isn't quite where I wanted, and I'm losing shots to the left and to the right. I need to do a little bit of work over the weekend and try and straighten it out. But I battled along nicely, and two under par putts me in a decent position going into tomorrow."

Still, the eighth was the talking point and McIlroy was happy to admit that his emotions got the better of him.

"Yeah, they did," he said. "It's just frustrating when you feel like it's quite close and it's just you're hitting balls in the water and you're doing things usually don't do. It's been funny, when I've been trying to hit a cut, I hit a draw; and when I try to hit a draw, I hit a cut.  It's just not quite there so just need to do a little bit of work over the weekend." 

The throw? A once off?

"... if you would have asked me this ten years ago as a moody teenager, it wouldn't have been out of character but I think I've mellowed since then.  Yeah, it was just frustration got the better of me."

And the game? No panic?

"It isn't far away. Just making silly mistakes and a couple ball in the water on the front nine and a couple putts on the back. I feel like I got a lot out of the round today considering how I played, but yeah, I'm just not 100 percent comfortable with it all at the minute and I'll just do a little bit of work over the weekend and try and straighten out. 

"I don't feel like I'm too far away.  It's a good start and all of a sudden you're into the top five at some point during the front nine tomorrow, so try and go out with that mindset but just need to figure something out. As you saw out there, it's quite frustrating at times." 

Out of kilter best describes McIlroy right now.

"I think every golfer feels it because I don't hit shots like the one I hit on eight on the range," he said. "So that's what really bothers me, the fact that I get out on the course and I hit shots that I'm not seeing when I'm in a more relaxed environment. So it's a little bit of mental, a little bit of physical.  It's just everything is not quite matching up."

Just seven players broke 70 with the round of the day a 68 by Adam Scott, wielding the short putter. The Australian had six birdies and two bogeys as he moved up to solo third, three shots off the lead on six under.