GOLF/PGA Championship: There are times in one's life when change is forced on you, when you know that things simply can't go on as they have been. For Darren Clarke, the moment arrived in the US Masters where he was leader after the first round before his descent down the leader-board - initially a slow one but thereafter with gathering pace - to 28th place hurt more than his pride and caused him to re-evaluate where he was headed, writes Philip Reid from Wentworth.

And one aspect of that weekend in Augusta, painfully obvious to him in hindsight, was that he simply wasn't fit enough. So it is that he has engaged a personal trainer, a man by the name of Barry Grinham who works with the Jordan Formula One drivers. It represents a sea change for him.

"(In the past), I didn't feel it was the right thing for me to do . . . but with me trying to identify reasons why I have not been playing as well as I should be, it is pretty logical to take a look at the one area I haven't addressed. That would be remiss of me if I didn't," he said.

Clarke's physical regime with the fitness coach hasn't started yet - the plan is to start next week - but the player has been adhering to a strict dietary programme involving a high carbohydrate intake designed to increase his energy levels.

"There were mistakes creeping in at the end of the round and they were happening too frequently for me to ignore," remarked Clarke.

"I basically wasn't fit enough to cope with the challenge, and I wasn't as mentally sharp as I needed to be. I wasn't in as good a shape as I needed to be."

Yesterday, on the West Course at Wentworth, where he feels very much at home, Clarke - munching energy bars - took a first-round lead for the first time since the Masters and didn't allow any errors to creep in. In fact, he played bogey-free golf, with not a sight of a three-putt, which is something of a rarity in Clarke's recent performances.

The result was that his six-under-par 66 was sufficiently good to give him sole leadership of the Volvo PGA Championship, an event he would dearly love to win. "It's high on everybody's portfolio to win, one that we all want to win. But it's only the first round, and there's an awful long way to go."

Of course, he's right; but on a day when a swirling wind added to the challenge, his lead over a trio of players - Alastair Forsyth, James Kingston and Thongchai Jaidee - has got the Irishman scenting what he feels is an overdue win.

For much of the past few months, nobody has swung the club better or played as well tee-to-green as Clarke.

Many of his problems, though, have arrived once he walks onto the green, and so he has started working again with the putting guru Harold Swash.

Yesterday, he missed only one green in regulation - the 15th - but still took 32 putts, still above the average, and the belief is that once his putter does heat up, then few will be able to stay with him. "I've had a cold putter now for about a year and a half and I'm just trying to weather the storm," he insisted.

Clarke's round was something of a slow-burner. He started with eight straight pars - missing a number of genuine birdie chances - but his play of the ninth proved his mind was very alert, with no frustration being allowed to creep into his mindset.

He played a low drive to keep the flight of the ball below the tree-line, and then punched in a six-iron approach to eight feet and holed the birdie putt.

On the way home, Clarke's patience was rewarded with a collection of three birdies and an eagle, which came on the 17th where he hit a five-wood second shot to 18 feet.

As Clarke knows, now he has to complete the job; and it won't be easy. Nowhere does the horses for courses theory work as much as it does here at Wentworth, and the names of Ernie Els and Colin Montgomerie are among those likely to threaten over the next three rounds. Both shot 69s yesterday.

For the most part, rounds were of a roller-coaster nature. Niclas Fasth, for instance, had a run of five successive birdies on the front nine - the harder half of the course - but slipped back to also sign for a 69, and the course's capacity to sit up and bite was further demonstrated by the 10 incurred by Mark James on the par four fourth hole.

Peter Lawrie, too, was mauled, suffering a triple bogey eighth on the 17th, where he put his second shot out of bounds, on the way to a 75.

Yet, the Irish challenge - led by Clarke, the first round leader - is not one-dimensional. Graeme McDowell continued his good form of last week by shooting a 68, while Ronan Rafferty (69) and Paul McGinley (70) also managed to shoot sub-par rounds in the tricky conditions.

McGinley birdied three of the last four holes to do so, and remarked, "they didn't come easy."

Rafferty's performance was almost reminiscent of old, even if he is suffering a little from a lack of tournament sharpness. This is only his fourth appearance of the season.

"As long as I keep the golf ball on the fairway, it's actually okay. I have been really, really struggling for two to three years now off the tee," he said.

Yesterday, though, the driver worked sufficiently well to put him in line to make back-to-back cuts, after surviving the mark in Hamburg last week.

Clarke, though, is the player who has got the scent of an overdue win. He hasn't won on tour since the English Open 11 months ago and the changes he has adopted since then - new caddy, new clubs, new sports psychologist, new diet and an impending new fitness regime - have been designed to turn him into a winner

At least he has completed the first part of the equation by taking the lead; the next part is to slot the other three parts into the jigsaw, which is the hard part.