The joy of sport is its never-ending propensity to surprise, and the opening round of the 2009/10 Heineken Cup proved no exception.

Holders Leinster kicked off the weekend with a shock 9-12 home reverse against London Irish in Pool 6, while French champions Perpignan were downed 9-8 by Italian minnows Benetton Treviso - who had lost their previous 10 home games in the competition.

Heineken Cup Pools & Fixtures

That last result apart - and we'll deal with that later - it was a decent opening round for French clubs with Stades Toulousain and Francais both opening with convincing home wins, while Clermont Auvergne did what was required against Viadana.

Biarritz's 22-18 away win at Glasgow Warriors also confirmed the Basques excellent current form, while Brive's 24-12 loss at Scarlets was to be expected too as the Limousin club continue to struggle.

The loss of Welsh back-row forward Alix Popham was a further blow for Brive, and life won't be any easier this weekend as they welcome defending champions Leinster to town, with the Irish side still smarting from last week's surprise home loss.

Another defeat could virtually end Brive's comeback campaign in Europe's premier club competition, but elsewhere there is plenty to be optimistic about. Stade Francais and Stade Toulousain both travel to England for tough away assignments - against Bath and Harlequins respectively - but victories are certainly not out of the question.

Perpignan have no option but to win, and win well, as they play host to ECC champions Northampton Saints, while Clermont journey to Wales for what could be a fascinating encounter against the Ospreys.

It's all set up for another cracking weekend, and the overall picture should become a lot clearer as teams jostle for positioning in their various pools.

Perpignan v Northampton Saints (21.00, 16/10/09, Pool 1)
The contrasting fortunes of these two teams on the opening weekend could not have been greater. "We touched bottom," admitted the French club's Romanian hooker Marius Tincu this week after they slumped to a potentially catastrophic away defeat at Italian side Benetton Treviso - the self-confessed minnows of Pool 1 - while Saints beat two-time Heineken champions Munster in a cracking match at Franklin's Gardens. The latter result will enable Jim Mallinder's side to approach Friday's game both confident and relaxed, knowing that anything they get from the match is effectively a bonus.

The Catalans, on the other hand, now have a massive gap to make up and know that they must strive for bonus-point home wins if they're to have any serious pretensions of making the knock-out stages. That alone heaps added pressure on Jacques Brunel's team, although it is not beyond them as they showed with their clinical 19-3 victory over Clermont Auvergne in their last home game.

Friday's match will be the first time Saints have played at the Stade Aimé Giral and Mallinder knows it will be a tough challenge. "It is a hostile place to play and their fans will create an intense atmosphere. But it is up to us to remain calm and stay focused on what we have to do," he said this week.

Fly-half Shane Geraghty won rave reviews for his performance last weekend, and Saints also have another potential match-winner in the shape of highly rated full-back Ben Foden. Both will depend on good ball as they attempt to shine, but Perpignan's home form has been solidly consistent - in sharp contrast with their away-day blues - and the Catalans will surely be keen to bounce back after their opening game humbling.

Scrum-half Nicolas Durand returns after injury ruled him out of the Italian fiasco, while rested duo Perry Freshwater and Jean-Pierre Perez are also back. Damien Chouly and Sebastien Chobet remain doubtful however.

Last week: Perpignan lost 9-8 away to Benetton Treviso.
Verdict: Perpignan win

Biarritz v Gloucester Rugby (14.35, 17/10/09, Pool 2)
In-form Biarritz will start as overwhelming favourites against Gloucester as they go into the Pool 2 clash riding high after six successive victories, including last week's 22-18 win in Glasgow. The Basques appear settled and confident after a sticky start to the season, and will be keen to make that seven consecutive wins as they entertain Gloucester.

Visiting captain Gareth Delve appreciates the size of the task facing the English side as they travel to the Basque heartland. "Biarritz are passionate guys and they've got fantastic home form. In fact, they're in fantastic form at the moment full stop," he admitted. "They're a superb team but we've got to back ourselves. We want to go there and look to win," added Delve.

Gloucester will definitely be without suspended French hooker Olivier Azam following his 12-week ban for kicking Steve Borthwick, while former Shed favourite Iain Balshaw sits out the visit of his old club due to torn abdominal muscles.

Last week: Biarritz won 22-18 away at Glasgow Warriors.
Verdict: Biarritz win

Brive v Leinster (16.45, 17/10/09, Pool 6)
If Brive's opening weekend defeat at Scarlets was to be expected then the same can surely not be said for Leinster's surprise home loss to London Irish. While the result itself could be viewed as good news for their Pool 6 rivals, Brive will now be mighty concerned about a Leinster backlash as they prepare to play host to the current Heineken Cup champions. The Irish side will also be aware that no defending champions have managed to retain their crown after losing their opening game of the competition, although Stade Toulousain did go on to make the final in 2004 after doing so.

"Everyone was very disappointed after last weekend's defeat, but we have come in and done a few good days work," said Leinster's defence coach Kurt McQuilkin this week. "We're in pretty good shape now," he added.

Brian O'Driscoll and company will be out to show last weekend's result was an aberration - the last thing a confidence shorn Brive really need as they struggle to find fluency with their own game. English fly-half Andy Goode lamented a late decision by Brive not to kick for goal and was also vocal in his criticism about their approach...

Goode's comments hint that all is not well at the ambitious Limousin club, and they are clearly not the same tight unit which battled so valiantly to qualify for this competition last season. A home win against the champions would surely go a long way towards rectifying that, but one fears for Brive as their season threatens to unravel amid the pressure of raised expectations brought on by high expenditure on the transfer market. 

Some fancy footwork from new Fijian winger Viliame Waqaseduadua wouldn't go amiss and the likes of Goode and Jamie Noon will also be desperate to put in eye-catching performances to boost their England claims ahead of the forthcoming November internationals.

Leinster's back row forward Shane Jennings will be absent after picking up a 12-week ban for eye-gouging in 12-9 defeat by London Irish.

Last week: Brive lost 24-12 away to Scarlets.
Verdict: Leinster win

Harlequins v Stade Toulousain (18.00, 17/10/09, Pool 5)
Stade Toulousain put an indifferent start to the new season firmly behind them with a resounding display against Sale Sharks last weekend. The French giants were in sumptuous attacking form as they raced 36-3 ahead before easing off the gas, and head coach Guy Noves believes the performance will prove a catalyst for their 2009/10 campaign.

The key half-back partnership of Byron Kelleher and Jean-Baptiste Elissalde thrived on the bounteous ball provided by their forwards, and with so much class in their backs it was men against boys at times. Sale's understrength side may have diluted Stade's achievement somewhat, but it's difficult to see how even a full-strength XV could have lived with the French side at times. If they can replicate that form in London then Quins are in for an extremely tough evening, but the Guinness Premiership outfit beat Stade Francais home and away in last year's pool stages, an achievement that will give them considerable confidence.

Danny Care and Nick Evans proved the hosts' half-backs, and their battle with Kelleher and Elissalde could be a fascinating encounter.

Toulouse winger Cédric Heymans is doubtful for the trip after injuring a shoulder against Sale, but the fact his replacement Yves Donguy scored a second-half brace of tries underlines the depth of quality the three-time champions boast. Clément Poitrenaud will definitely not travel either, but should begin his playing comeback with the Espoirs instead.

Last week: Stade Toulousain won 36-17 at home to Sale Sharks.
Verdict: Stade Toulousain win

Ospreys v Clermont Auvergne (12.45, 18/10/09, Pool 3)
Clermont's bonus-point home win against Viadana, coupled with their lead of Top 14, means 'Les Jaunards' can travel to Wales confident and relaxed. A losing bonus would probably suffice for Vern Cotter and his team, especially after the Ospreys drew 32-32 away to Leicester last weekend. That means priceless dropped home points for last season's runners-up, and could prove costly in a extremely tight looking group. The challenge this weekend for Clermont is to banish their traditionally poor away form - especially in European games - and to that end Cotter should be able to at least name his strongest available side.

He will be aware the Ospreys haven't lost at the Liberty Stadium in their last 10 Heineken Cup matches - and also beat Clermont there in 2006 - both the French outfit undoubtedly have the firepower to succeed with the likes of Top 14 Player of the Year Napolioni Nalaga and club captain Aurélien Rougerie in their attack-minded back line.

Clermont will be especially wary of Ospreys winger Shane Williams, the current IRB international player of the year who is relishing the Pool 3 encounter. "We certainly enjoy playing against the French, and Clermont have some tremendous flair players in a great back line. It is always a battle," he said. "We know Clermont are an excellent side and we will have to be on top of our game," added Williams.

Lee Byrne's injury means disgruntled fly-half James Hook could start at full-back against one of several teams currently rumoured to be interested in the Welsh international's services. The Ospreys will also be without injured prop Ian Evans.

Last week: Clermont won 36-18 at home to Viadana.
Verdict: Ospreys win

Bath Rugby v Stade Francais (15.00, 18/10/09, Pool 4)
Stade Francais started so well against Edinburgh last weekend they already had the attacking bonus tied up after just half an hour, but it's sure to be a tougher challenge at The Rec on Sunday. A clutch of British players will ensure the Paris giants have plenty of inside info on their opponents, and there's no doubt they travel to the west country looking for a precious away win to continue their excellent recent form. Bath, by contrast, have only recorded one competitive win so far this season and will view this game as the perfect opportunity to kick-start their faltering campaign.

The game takes on special significance for Bath head coach Steve Meehan - who this week agreed a new contract with the west-country outfit - as he was previously assistant at Stade Francais until coming to England in 2006. "It is something I've been looking forward to since the pools were announced," he admitted. Bath scrum-half and captain Michael Claassens is also wary of the threat posed by both of Stade's No 9 options. Last season Julien Dupuy's late try for Leicester condemned Bath to defeat at the quarter-final stage, while Noel Oelschig was a teammate of Claassens' back in South Africa.

Bath will be without suspended flanker Andrew Beattie, while if Stade Francais win on Sunday it will be their 50th victory in the Heineken Cup.

Last week: Stade Francais won 31-7 at home to Edinburgh.
Verdict: Stade Francais win