Impossible Things, Before Breakfast.

What on Earth happened?

Welsh rugby fans have become used to dizzying peaks and troughs, but even we now seem to have a case of national vertigo. Partly by accident of scheduling - it must be conceded - but mostly by unprecedentedly good play and management, Wales find themselves in their first RWC semi-final since The One That Doesn't Really Count, the only obstacle between them and ridiculous glory being a French side who have "done an England", by getting this far almost despite themselves.

Ay, there's the fly in the muscle-rub; France. Even worse, BAD France. It's a challenge to recall the last must-win game that France lost having started as underdogs. Dismissing their chances is like giving them a 15-point start. If the consensus holds that the French have one great game in them, then Wales are in trouble, as Les Bleus only spent about a quarter of that credit in seeing off England. There's still 60 minutes of invincibility left in the tank, then.

In a microcosm of the La-La-Land in which this Welsh squad find themselves, the replacement of last month's third-choice fly-half with the man most observers regard as the most creative player in the squad, is widely seen as weakening the Welsh team. Rhys Priestland has been the revelation in a tournament of revelations for Wales, and the success so far has given the lie to the traditional notion that Wales must play with an out-and-out playmaker at either #10 or #12. James Hook is now regarded with suspicion; his defensive imperfections highlighted, his oft-quoted difficulties with game-management pored over. The resurgence of Jamie Roberts as a midfield line-breaker - undeniably central to Wales' success -  is widely accredited to Priestland's presence. Hook's inclusion, forced by circumstance, looks likely to radically alter a system that was working just fine without him.

The French loose forward wolfpack will be looking to gorge themselves on Hook; but if they tire and leave gaps, as they did against England, there's no better card in the Welsh deck. Wales' bigger fear is a creative French kicking game, as their scramble defence is not yet up to the standard of their "first-up" tackling. If Médard and Mermoz can get up to speed against a back-pedaling Welsh three-quarter line, they'll back themselves.

So far, arguably Wales' greatest strength has been their refusal to panic when they concede. France will mix it up early on, and will certainly lead at some point in the match.  But if any Welsh side of the past generation is equipped to roll with the French punches, it's this one. Too close to call? Not really. If neither side raises their game significantly, Wales will win. It's France who have something to prove - and that should scare Wales silly.