Leinster are flying. Top of Pool Three, one of only four sides with 100 per cent records, and the discarding of another monkey off their backs has underlined their credentials. Never mind "could have been" or even "could be", they are contenders, writes Gerry Thornley.

It's not just the Donnybrook faithful who are getting giddy. Even Matt Dawson and Jeremy Guscott were agreeing with John Inverdale on Sunday's BBC Grandstand that Leinster are contenders, not least because they have the carrot of a "home" final.

All this talk won't amuse Matt Williams or the rest of the Leinster think-tank of course. They've won nothing yet, save for three games.

Yet, there's a professionalism about Leinster nowadays which is hardly likely to allow the merest hint of complacency, as evidenced by their whole approach to their Montferrand trip.

Williams himself had flown out with team manager Ken Ging and John West last July to check out everything from hotel facilities to training facilities and match venue.

Some of the Leinster technical staff had travelled over to watch and video tape Montferrand playing, and then again a few days beforehand to make sure everything was right and proper. A charter was hired, and DJ Carey was invited over to present the jerseys.

Hats off then to the Leinster management and even the oft-maligned Leinster Branch. The players were conscious of this going into the game and every little bit helped when generating the self-belief which enabled Leinster to hang tough.

"I think they had faith in the whole set-up and believed they could win, and I think that had a huge bearing on the outcome," said Williams.

As a result, Leinster are undoubtedly best placed of the Irish provinces after that magnificent win in France, a measure of which is the fact that Montferrand ran up 50 points against Northampton at home last season.

Yet, Leinster were in the same position at the half-way point in the pool stages last season, and were the first team to qualify for the last eight when winning the fourth game.

They then made it five out of five, only to lose their final pool match in Toulouse, miss out on a home quarter-final by two tries despite having 10 points, and ended up in Welford Road.

"That was some reward," as one Leinster player recalled on the trip home from Montferrand. So they know full well that, quite conceivably, once again the threshold may be 12 points.

By contrast, despite dipping their bread against Viadana to score nine tries last Friday night, Munster are still in Gloucester's slipstream in Pool Two. The performance level of the form team in England did, admittedly, drop a little bit when slightly flattered by their three tries to one, 33-16 win over Perpignan, but that merely shows how awesome their level of rugby has been this season - especially at Kingsholm.

Against that, Gloucester had a more intensive pre-season than most when touring South Africa and it is more than conceivable that they will not be able to sustain their imposing form all the way through to the April knock-out stages and beyond. You have to pace yourself over a season.

Furthermore, they've still to visit both of their main pool rivals, beginning with Perpignan next weekend. There was enough evidence from Sunday's televised, full-on collision, in which Perpignan appeared the victim of some home town refereeing which is characteristic of this competition, to suggest that the rematch will go down to the wire, much like Leicester's 31-30 win at Perpignan last season.

That also remains the only back-to-back double over a French side in the last two seasons, which shows what a difficult thing it is to achieve, all the more so (as Ulster will assuredly realise in advance of Saturday's return match in Biarritz) if you play them away second time around.

In any case, one can't help but feel that Perpignan beating Gloucester would be a significant favour for Munster.

Otherwise, Munster will also have to win away to Perpignan and then not only overcome Gloucester at Thomond Park in the pool finale, but also outscore them by four tries if Alan Gaffney's men are to top the pool.

It could yet be, at a push, that all three main contenders in this pool finish level on eight points, though this is an even more plausible scenario in Ulster's group, the ultra-competitive Pool Six where a three-way tie exists at the half-way point between Northampton, Ulster and Biarritz.

Ulster's problem is that they've only scored two tries to date, so topping this tight pool will be even more difficult for them, and it's highly unlikely that one of the two best runners-up will come from this pool, more likely Pools Two and Three.

With four defeats out of six, it was a damaging weekend for the French, though in most other respects the cream is rising to the top and the last eight could feature a heavyweight line-up featuring the big three from England - Leicester, Gloucester and Northampton - as well as Leinster and Munster, Toulouse and maybe Bourgoin, thus leaving Llanelli, at most, to fly the flag for Wales.

Listening to the fall-out from Neath's narrow defeat away to Beziers in October en route back from Munster's win over Perpignan in Limerick that same day, we heard the Neath coach Lyn Jones bullishly maintain that his side would win their remaining four games and qualify. Then we heard of their defeat to Calvisano on Saturday.

Oh, how we laughed.

The only blemish on the Irish provinces' weekend, of course, was Connacht's 42-27 defeat in Narbonne.

Theoretically therefore, Connacht's season could end next Sunday in Corinthian Park unless they beat Narbonne by 15 points, given there might not even be any interpros as, much like Connacht themselves, the IRFU haven't decided whether to abandon them or not.

Grist to the mill of the union's Connacht axemen? They're there alright, which prompts this column to point to the existence of a website petition in support of the western province.

To be found at www.petitiononline.com there are already nearly 800 signatures of support there.