IT’S D-day for Wales and for coach Warren Gatland at the Millennium Stadium today when they take on world champions South Africa.

The teams face one another for the 23rd time and Wales have won only a paltry once, back in 1999 when the stadium was barely half full because rebuilding was still going on.

Now they need to build on their Grand Slam achievement of last season by proving they can make the next step, which means getting the better of a southern hemisphere giant.

And the stakes are just as high for coach Warren Gatland who has made it plain he wants to test himself at a higher level as well.

Bearing in mind his appointment as forwards coach for the British Lions in South Africa next summer, it would be a feather in his cap and a major motivational weapon for the Lions if he can get one over on the Springboks at this stage.

But can Wales and Gatland go that extra mile today? That’s the question on everyone’s lips as they converge on the capital with maybe more expectation than hope this time.

That is based on two factors. First Wales proved they have that winning mentality after rising from the ashes of the World Cup to go all the way to the Grand Slam a few months later.

And Gatland’s stock rose sharply by turning things around so swiftly that Wales scaled the northern hemisphere heights with virtually the same players who suffered World Cup humiliation at the hands of Fiji in France.

So Welsh hopes of gaining an elusive southern hemisphere scalp are high - and they have been further helped by a certain disarray in the South African camp, scarcely credible though that may be a year after reaching the ultimate peak with their World Cup triumph.

They achieved it by playing to their traditional strengths of forward power allied to an astute kicking game and a tight defence, all marshalled by inspirational coach Jake White.

But White left and in came Peter de Villiers, the first black man to coach the Springboks.

And with him came a change of style with de Villiers favouring a more expansive approach after learning his trade in Wales when he initially stood on a touchline unannounced, paying his own way to take part in the WRU coaching courses.

There he struck up a lasting friendship with John Prince of Blaenavon, WRU assistant technical officer in the nineties, and the pair were reunited this week.

De Villiers has favoured a different style, and it hasn’t been universally popular back home, especially after South Africa finished bottom of this year’s Tri Nations table.

So he is very much on trial and the outcome of today’s game could have a considerable bearing on his immediate future.

For defeat would be regarded as catastrophic – when it happened on the one and only occasion just over nine years ago it resulted in the demise of skipper Gary Teich-mann and his subsequent arrival at Newport.

Any uncertainty in the South African camp will be seized upon by Gatland and could prove the foundation of his all-important team talk before he sends his side out for battle.

And that is exactly what it promises to be, for whatever system the coach may favour the Springbok team is so battle hardened that it is inconceivable they won’t adopt a hard headed approach up front.

Even there, though, there could be a chink of light for Wales with the surprise decision to switch World Cup winning captain John Smit from hooker to tight head – a situation the 60-times capped Gethin Jenkins could exploit.

But there are so many big time players in the hard core of their pack – mighty locks Bakkies Botha and Victor Matfield boasting 129 caps between them with Smit on 78 and flankers Juan Smith and Schalk Burger on 52 and 46, respectively.

Compare that combined total of 305 with 190 by their opposite numbers, and almost half of those are provided by one man, Martyn Williams on 81.

There has to be a fear the awesome second row partnership of Botha and Matfield will be too formidable for Wales, especially as the Ospreys line-out has malfunctioned this season, and Ospreys trio skipper Ryan Jones, Ian Evans and Alun Wyn Jones provide the bulk of the Welsh line-out, though caller-in-chief Jonathan Thomas is missing.

It promises to be a baptism of fire for new boys Andy Powell and Leigh Halfpenny, Powell up against a formidable Springbok back row with the task of proving he has the temperament to match his undoubted drive while Halfpenny is only up against the jet propelled Bryan Habana.

Halfpenny becomes the 60th teenager to be capped by Wales, the last being fellow Cardiff Blues player Chris Czekaj against Canada in 2005, and it is vital he closes Habana down for he is the big danger for Wales, though Jean de Villiers is a class centre – and there is always Frans Steyn to bring off the bench when many believe he should be starting.

But Wales have their own flier Shane Williams who seems to get better with age. He turned Habana inside out on the summer tour and he has the formidable strike rate of 43 tries in 58 appearances for his country.

Wales have got to get the ball away from the fearsome Springbok pack or it will be game over, and releasing Williams ought to be their main objective if they are to win the game.

Jamie Roberts can also do some damage with his powerful running and make it a double celebration for he becomes the 29th player to appear in an international on his birthday - he’s 22 today.

A year ago it was the Springboks who celebrated an anniversary – 100 years of matches between the rivals and they walked away with an impressive 34-12 victory and a try count of five to two without really breaking sweat.

The margin may not be as high this time, but the outcome could have a depressingly similar ring to it - South Africa to win, by around 10 points.