To lose one world-class, game-breaking, low-sense-of-gravity, line-straightening, try-scoring Lions midfield shoo-in might be considered unfortunate, but to lose two would be downright cursed.

You get the feeling this is going to be a decidedly fluctuating and fickle Six Nations campaign, but aside from the reverberations at the Millennium Stadium on Saturday, nothing had quite the same ripple effect from the opening round of games than the injuries to Brian O'Driscoll and Gordon D'Arcy.

Good husbandry had ensured Ireland went into the championship in better health than anyone else but thereafter Ireland's title credentials, more so even than England and France, hinged on remaining healthy. Alas, having rejoiced in Ireland finally being able to field all their back-line galacticos in the same match for the first time, the unveiling lasted barely half an hour. Neither of the stricken midfield maestros attended the post-match banquet, but their injuries - far more than the widespread acknowledgement that Ireland would have to improve their performance level - appeared to leave no one in any mood to don a black tie and celebrate.

Ireland could conceivably have taken one hit, bearing in mind how the strong-running, in-form Shane Horgan reverted to midfield in the autumn and for 50 minutes on Sunday in the Stadio Flaminio, but two would seriously blunt the most potent back line in Europe. Even by 20 to 30 per cent is probably a conservative estimate, and that's leaving aside O'Driscoll's presence as squad standard-bearer and talisman.

You only have to think back to last season's Triple Crown winning campaign: O'Driscoll's two-try comeback against Wales after a five-week absence from a near identical-looking hamstring tear; D'Arcy against England at Twickenham; O'Driscoll at home to Italy and D'Arcy against the Scots, not to mention O'Driscoll on Sunday.

Hamstrings are such variable injuries, and sometimes such unpredictable healers, that no less than anyone else the team doctor Gary O'Driscoll was unwilling and unable to make any firm prognosis on Sunday night pending yesterday evening's scans. But it would be a minor miracle if either trundled out next Saturday in Murrayfield, and certainly, you'd have thought, they'll be pushing it for the French game five weeks' from now at best.

Eddie O'Sullivan must be cursing his luck, but he has no option but to put his and Ireland's best foot forward. As in Paris last year, that would begin with reinstating Paul O'Connell as captain, and those punters who've backed him to be Lions skipper will be double checking their betting slips for henceforth he's liable to be more than just a dark horse for the job. Recalling Kevin Maggs alongside Horgan looks the likeliest midfield option, though that has a sameness about it which mightn't appeal. Ideally, the Irish coach would like more of an individualistic spark there, perhaps Geordan Murphy. Apart from the one-off experiment in Perth the summer before the 2003 World Cup, outside centre is unfamiliar terrain for him, and it would mean sacrificing his freer, more roving attacking role from full back.

Shaun Payne - who has played at outside centre half a dozen times for Munster this season - still looks more at ease with himself on the wing. O'Sullivan has never been an obvious fan of Mike Mullins, Mark McHugh has returned to health and form with Connacht but like Payne is unproven at this level, and John Kelly, who made his return from injury at club level for Cork Constitution at the weekend, has even less. Anthony Horgan and Tommy Bowe will come into the equation on the wing, with the latter more comfortable on the right flank than Horgan or Denis Hickie.

In any event, no one would appreciate the loss of O'Driscoll and D'Arcy more than Matt Williams and Willie Anderson. Buoyed by Scotland's resistance in Paris on Saturday and a lingering sense of injustice (though Williams' post-match outburst perhaps masked the limitations of his side's performance as well as the extensive pressure he is under for a win), they, their players and fans, will be even more convinced they can stifle Ireland at home.

In the midst of all this, D'Arcy's Lions credentials especially have taken an untimely dent. Meanwhile, of course, Gavin Henson is emerging as the midfield golden (or silver) boy of the tournament. The embodiment of new Wales, much as O'Driscoll is for Ireland, he's cocky in an engaging sort of way as well as being touched by God to play rugby. It may be apocryphal, but the word is when he gladly assumed the responsibility for that match-winning penalty, Henson said to his captain Gareth Thomas "start celebrating".

England were comparatively directionless in midfield. The blind faith with which some pundits put the flaky Charlie Hodgson above Ronan O'Gara in the Lions pecking order was again put into context by the manner O'Gara, in contrast, overcame his line-kicking difficulties (a one-off) with the Italians' Mitre ball to nail his goalkicks and launch the Irish backs.

Aside from a more complex breakdown area, less continuity and fewer tries, another abiding feature of round one was that England, Wales, France and Italy probably all started out the championship with the wrong goalkickers. England were also devoid of a Test-quality kicking game to play to their pack until Ollie Barkley's belated introduction suggested they might pilfer an underserved win. Barkley will surely start against France next Sunday.

Overall though, the weekly Lions speculation (Martyn Williams for openside?) is becoming a little tiresome, no? For it is abundantly clear the amalgam of intensity and competitiveness will make this a more fickle, ever-changing sideshow than ever before, and compelling in its own right.

More than anything, you wonder how the Gods could be so cruel to Ireland, of all teams, and two of its likeliest match-winners, in of all places Rome. Yeah, you think back to a heading on a column in the London Independent last week. "Knowing the luck of the Irish, my money is on France." Hmm. Although the French have the choices and talent to overcome a typically sluggish start the Bernard Laporte reign seems to be in an irretrievable slump and now dependent on the mercurial talent of Frederic Michalak for immediate revival.

England to win next Sunday, but already it is no longer "le crunch".