Phil Mickelson claims to have kicked the gambling habit, so we can forgive him if he was ignorant of the odds that ranked a Tiger Woods grand slam more likely than a Mickelson win at the Masters. Had he known, the world’s best leftie might have been entitled to abandon his folksy California charm and rage at the insult.

Woods is attempting an unprecedented feat, one of historic proportions — the scale of which has looked more daunting with each day at Augusta. Mickelson is merely trying to pull off what he has managed twice before, in 2004 and 2006, to win green jackets.

“What about me?” he might justifiably have asked when he came into the press room this week and faced questions about Woods’s march on history. Instead when pressed on the “slam”, he said it would be “pretty cool”. Now he might just be the man to stop the Tiger in his tracks.

Mickelson was the big beast on the leaderboard yesterday after a second-round 68. But if there was no sign of Woods in the top ten, he was not lurking far below. A tap-in for birdie on the 17th and a scrambled par on the last, played via the 10th fairway, put the world No 1 at one under par. If he has not played like a history-maker, he is still in touch.

Woods is four behind Mickelson, although the gap might have been wider had the world No 2 converted good birdie chances on the 15th (a simple four-footer), 16th and 18th. Harsh self-reproach was probably not called for, given that Mickelson had managed that rarity around this brutally long Augusta track — a bogey-free round.

The luck seemed with him right from the first hole of the tournament on Thursday, when he drove into the trees, missed the green and then “thinned” a chip that could have scuttled halfway to Alabama had it not clattered into the flag and dropped in for a birdie. “That was a two or three-shot swing right there,” Mickelson said.

The significance of that good fortune became fully apparent only as he joined the leaders yesterday — and Mickelson detected more good vibes. “In 2004 when I hadn’t won a major, I hit a shot at 13 we thought had gone into the creek, but I ended up making four. I’ve hit a couple again that should have been in the creek, but both of them stayed up. I am taking that as a good omen.”

There are more practical reasons to fancy Mickelson to be there or thereabouts. While he joined the chorus of players who believe that lengthening Augusta has taken away some of the excitement, it remains a venue that he relishes. “I love this golf course. I love this tournament and I love that you don’t have to be perfect when you get here,” he said.

His form has been less than spectacular in recent weeks but the tutelage of Butch Harmon since last year has paid dividends with a shortened swing and improved accuracy. Mickelson has also improved his fitness, with one onlooker greeting a missed putt by yelling, “That’s OK, Phil, you’ve got the best rack of any guy out here.”

Perhaps the hardest challenge has been shaking off his awe of Woods, something he took a small but significant step to achieving last September when, assisted by Harmon — the man who helped to launch Woods to greatness — he beat him in the Deutsche Bank Championship.

“It feels terrific,” Mickelson said after that victory. “For ten years, I’ve struggled against Tiger. This sure feels great to go head-to-head.” He added that “the next thing will be to pair up with him and do it in a major”.

Bring on the Tiger? He might have to be careful what he wishes for after Woods walked off the 18th with a purposeful look last night.