GOLF:THE METAMORPHOSIS, determined primarily by the weather, has been pronounced. Rather than the beast which devoured practitioners a year ago, the pristine course here has offered a kinder and fairer test to the midpoint of the 72nd US Masters, where Trevor Immelman, just months after undergoing surgery for a rare tumour, manoeuvred his way to the outright lead.

On a beautifully sunny day, but with a swirling breeze around Amen Corner to accentuate the challenge, there were, however, predictable manoeuvrings from others with major ambitions, those you'd expect to be in the thick of things.

Namely, a certain Phil Mickelson; a certain Retief Goosen; and, less obviously, a certain Tiger Woods.

Indeed, for the second day running, players didn't walk off the course battered and bruised by what they had encountered. Unlike a year ago when birdies, and especially eagles, were designated some kind of rare breed, those who attacked with cunning and used soft hands on the putter were rewarded.

While Pádraig Harrington was involved in a fight for survival - a front nine of 38, with three bogeys and a lone birdie, left him on the predicted cut mark of four-over-par as he entered the back nine - the European challenge was kept very much alive.

It was spearheaded by Ian Poulter, who returned a second round 69, for 139, three strokes behind Immelman. Paul Casey, too, moved into contention with a 69 (for 140), while Lee Westwood, despite missing a short birdie putt on the last, signed for a 73 to be on the 143 mark.

If Immelman were to look over his shoulder, the most threatening name on the leaderboard behind him would be that of Mickelson's. Yesterday, as he has done in the past on the way to two green jackets, in 2004 and 2006, both even-numbered years for the superstitious in the galleries, Mickelson signalled his intent with a bogey-free round of 68, moving him to within three stokes of the midway leader.

"I put the ball in the spot where I was able to make easy pars, that would be one key (to the round)," admitted Mickelson. "You want to stay close to the leaders. You don't want to make any big mistakes and get way out. If you're falling behind, you've got to be more aggressive . . . I was fortunate where I was, not too far back, and didn't have to make a lot of tough decisions."

In other words, Mickelson stuck to as simple a gameplan as he could. Of course, he was helped by a hot start that saw him birdie the opening two holes, with another on the eighth to turn in 35 strokes. His only birdie on the homeward run came on the 17th, where he sank a 30-footer.

Of his position, Mickelson, a tad greedy, said: "I feel pretty good. I'd rather be leading, and I'd like to have some shots in hand. But I've hit the ball well. I'm only a few shots off the lead."

Immelman, who has recorded just one bogey in 36 holes, heads into the weekend with a one-stroke lead over American Brandt Snedeker, followed by a pack that features Poulter, Mickelson and another left-hander, Steve Flesch.

One man undaunted by the challenge posed by Augusta was Poulter. On Friday, his hole-in-one on the 16th highlighted his round and, yesterday, dressed in pink trousers and more akin to the Pink Panther than a tour golfer, the 32-year-old Englishman produced a patience on the course that contrasted sharply with his attire.

While a hole-in-one on the 16th elude him yesterday, Poulter did manage a birdie there. "The 16th has been nice to be. I mean, to play it in three shots in two rounds. Lovely! I'm looking forward to the weekend now. I've been very solid the last two days, am very happy with my ball striking and how I'm hitting it.

"We'll see what happens over the weekend. I fully believe in my ability, and if I play like I know I can play, then I'm sure I can give myself a chance."

There was a similar level of confidence from Casey, who has put two sub-par rounds together for the first time in the Masters.

"I've always put myself behind the eight ball in the past and I've had to battle and pull a number out the bag to make the cut. So it's slightly different this time."

Casey, who spent two weeks in Arizona with his coach, Peter Kostis, ahead of the season's opening major, added: "I had hoped my game was coming around. I really haven't played very good golf so far this year. I haven't struck the ball or scored particularly great, but I was really looking forward to coming here and getting the major season started."