The Newport Gwent Dragons, Cardiff Blues and Ospreys were drawn in Pools One to Three respectively, with Llanelli Scarlets drawn in Pool Six. With the final set to be staged at the home of Welsh rugby, Cardiff’s Millennium Stadium, there was great expectation that the possibility of a home advantage in the final would spur on Welsh advancement to the latter stages of the tournament.

For the Cardiff Blues the prospect of reaching the final 'next door' was particularly mouthwatering as was the chance to emulate Cardiff RFC's original European feat of reaching the inaugural Heineken Cup Final at the Arms Park ten seasons previously.

The Newport Gwent Dragons faced Castres Olympique and Munster, two tough opponents that the Ospreys had encountered the previous year, as well as Guinness Premiership outfit Sale Sharks. The Dragons travelled to France for their opening encounter and were just short of the mark as they suffered a narrow loss on foreign soil. Castres led 14-3 at half-time at the Stade Pierre-Antoine largely due to the dominance of their forwards but Gareth Cooper scored the Dragons first try of the tournament soon after. Sloppy play allowed a fourth French, gaining the side a bonus point, but the Welsh region responded well to send Gareth Wyatt over for a brace of tries. With the score fixed at 29-24 the Dragons were unable to scrape the win but took away a losing bonus for their efforts. The Welsh region hosted Sale Sharks at Rodney Parade in the second match of the tournament. The Guinness Premiership side overpowered the Dragons in a five-try showing that earned them a bonus point to stretch their lead at the top of Pool One. Though Gareth Wyatt kept up his try-scoring form, despite the Dragons’ depleted team sheet through two sin-binnings, his effort was nullified after two late Sale tries that completed the 11-38 scoreline.

In the second home tie at Rodney Parade the Dragons were once more outclassed on their own stomping ground. Irish giants Munster drew out a 17-3 half-time lead and continued to increase the deficit through the ever-reliable boot of Ronan O’Gara. An injury time try from Gareth Chapman proved too little too late for the Dragons who had run out of steam; their Heineken Cup hopes had been truly extinguished in this defeat. Just seven days later the Dragons travelled to Thomond Park and encountered a second defeat at the hands of eventual champions Munster. The Gwent region trailed by only two points at the break and after the restart took the lead courtesy of a Kevin Morgan try and Ceri Sweeney’s boot. Yet the Irish fought back with two quick-in-succession penalties from O’Gara; an injury time try put the Munster victory firmly out of doubt.

January 2006 saw Round Five of the competition and another away fixture for the Newport Gwent Dragons. Sale Sharks notched up a 30-10 win at Edgeley Park; the bonus point resulting from their four tries pushed the Guinness Premiership side into a quarter-final position in the competition. Tries from Sebastian Chabal, a brace from Mark Cueto and one from Charlie Hodgson, that took his personal points haul to fifteen, outdid the Dragons’ two tries from Richard Fussell and Sione Tuipulotu. The defeat ensured the Dragons remained rooted to the foot of the Pool One table with just a single point from five fixtures. In the final contest the Dragons clawed back some self-respect in a bonus point win over Castres Olympique at Rodney Parade. The Dragons gave a powerful first-half performance to take a 20-0 lead into the break. Ian Gough scored the Dragons’ fifth try in the fifty-seventh minute to stretch the lead to 25-3 yet the French side launched a comeback to narrow the final score to 28-17. Craig Warlow kicked a late penalty for the Welsh region to secure the victory and ensure the Dragons did not exit the Heineken Cup competition with a whitewash.

Cardiff Blues launched their 2005–2006 Heineken Cup campaign with an emphatic 40-13 win over Leeds Tykes at the Arms Park. The English side led 6-13 at the interval but failed to score a single point in the second half as the Welsh side turned the game around. They notched up four tries in the second-half, including a brace for hooker Gareth Williams, whilst Nicky Robinson added to the Blues’ tally as his on-form boot amassed a personal haul of twenty points. This bonus point win put the Blues on top of Pool Two at this early stage as they headed into the second round clash with Perpignan; the pool favourites. The fifth-seeded team lived up to expectations as they recorded a 37-14 victory over the Blues at the Stade Aime Giral. The Blues experienced a woeful first half in which they were unable to score, going into the break eighteen points adrift. The Welsh side rallied in the second half but conceded an additional three tries to the two already scored, giving the home side a bonus point. Belated tries from Jamie Robinson and Rhys Thomas softened the blow slightly but the Welsh region had looked second best throughout the match.

Round Three's tie with remaining Pool Two opponents Calvisano proved a more successful event for the Blues in a game in which Jonah Lomu made an appearance in his first competitive match in almost three years. The All Black played for sixty minutes in the Blues victory as they scored four tries to take away a winning bonus point. Robert Sidoli began the Blues' scoring after seven minutes but the home side responded in kind just five minutes afterwards. The Blues took a 10-13 lead into the break and put the victory out of doubt after an hour as Mike Phillips set both Rhys Williams and Chris Czekaj up with tries. Nicky Robinson could have increased the Blues score but missed four out of six attempts with the boot but as Calvisano failed to add to their ten points in the second half the Blues achieved their 10-25 win with little difficulty. In the return fixture in Cardiff the Welsh side inflicted a greater margin of defeat over the Italians. In Jonah Lomu’s debut at the Arms Park, Cardiff inflicted the Blues on Calvisano in a six-try showing with a brace each for Xavier Rush and Rhys Williams. The Italians achieved two tries which were little more than consolatory in the 43-16 defeat.

The Blues entertained Perpignan at the Arms Park in the Round Five clash of the competition. The visitors inflicted a damaging 3-21 defeat, courtesy of Jean-Phillipe Grandclaude and David Marty, as the home side were only able to attain a penalty from the boot of Nick Macleod. The defeat left the Blues aiming for a hefty win over the Tykes to possibly secure a second place, runners-up route to the quarters. Yet it was Leeds who delivered the substantial defeat as they ran in seven tries to nil in a 48-3 victory. The win put them second in the Pool table but they failed to secure one of the runners-up quarter-final berths due to results in other pools. The Tykes ran in three first-half five pointers before securing their bonus point early in the second half. The Blues could only respond through one Nick Macleod penalty and never threatened the Leeds line as the home side continued the rout until the very last minute, bagging an injury time score. Despite the successful beginning to the competition the Cardiff Blues fell at the last hurdle with two disappointing defeats, putting them out of the tournament at the pool stage once again.

The Ospreys were drawn in Pool Three against Heineken heavyweights Stade Francais, the Leicester Tigers and Clermont Auvergne. In their initial match the Welsh region met the previous competition’s runners-up and secured their first victory of the tournament. Sonny Parker secured a first-half try for the Ospreys, giving the home side a 10-3 advantage as the teams headed into the dressing rooms. Lucas Borges attained a try for Stade Francais in the second half but due to the unreliable kicking of Juan Martin Hernandez, who missed four chances throughout the game, the Ospreys kept the French at arms length. Matthew Jones secured a penalty for the Ospreys who had a nervy final ten minutes but managed to retain the fragile 13-8 win. The Welsh region were unable to defeat the other French side of the pool as they travelled away to take on Clermont Auvergne. Despite Shane Williams’s early try the Ospreys were outshone by Clermont as they secured four tries for the bonus point with Wales’s Stephen Jones adding fourteen points of his own in the 34-14 French win.

Round Three saw another loss for the Ospreys, this time at the hands of the Leicester Tigers. The visiting Ospreys led 6-12 at half-time through tries from Sonny Parker and Adrian Cashmore but a second-half comeback saw the Tigers clinch a 30-12 turnaround victory. Brett Deacon, Harry Ellis and George Chuter all attained tries as Austin Healey grabbed a fourth for a crucial bonus point in the dying minutes of the game. The Ospreys were unable to add any points in the second half so remained with one win from three in the competition thus far. In the second clash between the two rivals at the Liberty Stadium, a last-minute try from Dan Hipkiss sealed a narrow Tigers’ win. Barry Williams secured a first-half try for the Ospreys who took a 10-3 lead into the break. Shaun Connor scored the second Welsh try in the second half and as the Tigers were depleted to thirteen men a home victory looked likely. Yet a combination of poor Ospreys kicking and late Tiger tries secured a narrow 15-17 win for the English side, promoting them to the top of the pool table whilst at the same time ending Ospreys’ quarter-final hopes.

The Ospreys entertained Clermont Auvergne at the Liberty Stadium a month later and enacted revenge for their earlier defeat in the competition by the French side. Adrian Cashmore successfully kicked sixteen points in the Ospreys’ 26-12 win; a game in which neither side could progress further in the competition. Richard Mustoe and Stefan Terblanche scored tries for the Ospreys to lift them off the bottom of the Pool Three table as they headed into the final round game with Stade Francais. Hoping to do the double over the Parisians the Ospreys instead suffered a record defeat. The French side, aiming for a last-eight berth, increased their chances of a runners-up pool position as they put seven tries past the Welsh region. Matthew Jones added a consolation try in the second half but the Ospreys were not able to overcome the 24-3 half-time deficit. Stade Francais pushed the final score to 45-10 but were ultimately not able to make the quarter-finals despite the rout inflicted on the Neath-Swansea region.

The Llanelli Scarlets met defending Champions Toulouse in Pool Six along with Edinburgh Rugby and the London Wasps; the second year in a row that the Scarlets had been drawn against the French side. The Scarlets travelled to the Stade Ernest Wallon for their tournament opener in which the French title holders dominated the play and scoreline. Though two penalties from Gareth Bowen secured an early six point advantage for the Welsh region Toulouse put three tries on the board before the half-time whistle to lead 24-11 at the break. Just seven minutes after the recommencement a fourth French try secured the bonus point. Although tries from Hottie Louw and Matthew Watkins reduced the deficit the French rounded off their triumph by taking their try-count to seven at the full-time whistle. Looking to build on this 50-28 crushing defeat the Scarlets hosted Edinburgh at Stradey Park in the second round match but only narrowly secured a victory. Edinburgh took a 7-5 lead into the break after a converted Scott Murray try; Alix Popham secured a five pointer to keep the Welsh region in contention. Chris Paterson secured two penalties in the second half, the latter on seventy-eight minutes to edge the Scottish lead, but a try from Dafydd Jones nine minutes into injury time forced the score to thirteen points apiece. Gareth Bowen’s nerve held as he successfully delivered a conversion and clinched a Scarlet victory.

The Scarlets secured their second successive win of the competition in their home fixture against the London Wasps. The English side took a slender 3-6 lead into the break yet on the resumption Dafydd James scored a try for the Welsh region, followed by a superb five pointer from Mark Jones shortly afterwards. Tom Rees pulled a try back for Wasps but late penalties from Gareth Bowen ensured the Scarlet victory and denied the London outfit a losing bonus point. In the return fixture just seven days later the London Wasps cemented a 48-14 demolition of the Scarlets at the Causeway Stadium. Tries from Tom Voyce, Josh Lewsey and George Skivington for Wasps and one from Scarlet Matthew Watkins took the half-time score to 27-7. In a powerful second half display the Guinness Premiership side added three more tries; Voyce completed a hat-trick whilst French international Raphael Ibanez added the other. A late try from Barry Davies added to the Scarlet tally but the Welsh region had received, in the words of coach Gareth Jenkins, ‘a walloping’.

A Murrayfield meeting of Edinburgh and the Llanelli Scarlets set up the Welsh side’s fifth game in the Heineken Cup tournament. First-half tries from Matt Mustchin, Andy Kelly, Mike Blair and Hugo Southwell secured a 26-13 half-time lead as the Scarlets could only reply with one try and two penalties. Tries from Alix Popham, Lee Byrne and Tal Selley reduced the deficit but a fifth try for the Scots in the second half pushed Edinburgh into a slight 33-32 lead that the Scarlets were unable to overturn. In their final pool game, the Scarlets hosted Toulouse at Stradey Park as the reigning champions just edged out the Welsh region. This six-try win guaranteed the French side a home quarter-final fixture but the Scarlets put up a valiant fight throughout to keep the scores close; the game finished 42-49. The West Wales region initiated the scoring as Barry Davies crossed the Toulouse line after just forty-seven seconds. Vincent Clerc added two tries with Isitolo Maka adding another for the French side before a converted try for each team rounded off the first-half scoring at 29-23 in favour of the visitors. Clerc completed his hat-trick soon into the second half whilst former All Black Regan King added a Scarlet try to make it 30-39. Clerc powered over for a fourth but was matched by Welsh scrum half Dwayne Peel and Davies, having opened the try-scoring, closed the try-count with his second of the game. Toulouse hung onto their seven point lead to gain a quarter-final berth as the Scarlets failed to advance to the latter stages.

For the second successive tournament the Welsh regions failed to progress to the latter stages of the Heineken Cup. The Irish were victorious over the French in the final outcome, as European rugby's most prized possession came to a climax at the Millennium Stadium in Cardiff, preserving a modicum of Welsh flavour in the tournament as the home of Welsh rugby provided the arena to stage the final contest.

After seasons as the nearly men, including two near-misses as runners up; one of which had been at the Millennium Stadium against Leicester Tigers in May 2002, Munster, who had topped their Pool, beaten Perpignan in the quarter-finals and then emphatically dominated a semi-final derby against Leinster, defeated Biarritz Olympique in a pulsating match. Nearly fluffing their lines after gifting Biarritz an early try, Munster took the match by the scruff of the neck and fought back to win the try count 2-1 as Ronan O'Gara slotted over five perfect place kicks.

Under the electric atmosphere of a closed roof and in front of a crowd of 74,452 with a sea of red that made it look like a Wales home game, Munster lifted the Heineken Cup trophy for the first time in the tournament's history.