LEINSTER
Fixtures: Racing (a), Gloucester (h), Gloucester (a), Racing (h).
Euro pedigree: Four-time champions in 2009, 2011, 2012 and 2018, and beaten finalists in 2019 and last year.
Formguide: That 14-man comeback win by 38-29 over Ulster made it nine from nine.
Key player: In the latter stages especially Johnny Sexton’s leadership as well as his all-court game will be key, but Ross Byrne has proven to be an able understudy.
Odds (Paddy Power): 9/4 favourites.
Prospects: Acute desire to win that fifth star and have the added incentive of the final being in Dublin. Beat Racing away and would be well set up to secure home advantage in the knock-out stages.
[ Tadhg Beirne at one with Munster’s heart and soul ahead of European campaignOpens in new window ]
MUNSTER
Fixtures: Toulouse (h), Northampton (a), Northampton (h), Toulouse (a).
Euro pedigree: Champions in 2006 and 2008, beaten finalists in 2000 and 2002.
Formguide: After losing five of their first seven, Munster have won their last three, including a momentous victory over a South African A side. Last week’s comeback win Edinburgh was their best performance of the season.
Key player: Peter O’Mahony. Talismanic leader and aerially superb, when he went off in the 63rd minute of last season’s quarter-final against Toulouse Munster were leading 24-14.
Odds: 22/1.
Prospects: Some timely momentum but so much hinges on beating Toulouse tomorrow, not least as their pool finale is the return tie.
ULSTER
Fixtures: Sale (a), La Rochelle (h), La Rochelle (a), Sale (h).
Euro pedigree: Champions in 1999, beaten finalists in 2012, but one quarter-final in last eight.
Formguide: Scoring freely through their maul and potent backs, but a second loss to Leinster, and from 22-3 up with a man advantage, could leave scars.
Key player: Stuart McCloskey. So much of Ulster’s attack revolves around his ability to carry over the line, but also his passing range and offloading.
Odds: 25/1.
Prospects: Losing that semi-final in Cape Town last June has contributed to a brutish draw. Away to in-form Sale tomorrow, but Ulster have won five of their last seven in England.
TOULOUSE
Fixtures: Munster(a), Sale (h), Sale (a), Munster (h).
Euro pedigree: Five-time winners in 1996, 2003, 2005, 10 and 2021, runners-up to Wasps in 2004 and Munster in 2008. European aristocracy.
Formguide: Lead the Top 14, winning seven of their first eight before the international break interrupted their momentum but back to winning ways last week when springing Antoine Dupont and 163 caps of talent of the bench for the last half hour.
Key player: Dupont. Toulouse have a surfeit of X factor but this all-round generational player has all the basics and that in abundance.
Odds: 6/1.
Prospects: Contenders again although could drop points away from home, which might impact them in the knock-out stages.
LA ROCHELLE
Fixtures: Northampton (h), Ulster (a), Ulster (h), Northampton (a).
Euro pedigree: Reigning champions from just their fourth campaign last season, and beaten finalists the season before. The new force on the block.
Formguide: Not exactly flying. Poor loss against Stade Francais, their third in five games, saw Ronan O’Gara’s men drop to fourth below the Parisians.
Key player: Grégory Alldritt. Antoine Hastoy looks a classy acquisition from Pau in solving their out-half issues, but Alldritt is the man who makes the hard yards.
Odds: 7/1
Prospects: Huge squad, reasonably good draw and O’Gara has helped infuse them with a love for this competition, but will the first still burn as much?
RACING 92
Fixtures: Leinster (h), Harlequins (a), Harlequins (h), Leinster (a).
Euro pedigree: Three-time beaten finalists in the last seven seasons, making them the new Munster/Clermont.
Formguide: Have won their last five, averaging 40 points per game, to rise to second in the Top 14.
Key player: Finn Russell. In imperious form, with a 92 per cent kicking ratio to stand second in the Top 14 points scoring charts. With his array of passes and kicks given full rein, when he’s good, Racing are invariably good, but….
Odds: 17/2.
Prospects: Moving their opener to Le Havre to accommodate a concert doesn’t sit with their Euro ambitions. Lose and they might have to beat Harlequins twice. Should reach knockout stages though.
GLOUCESTER
Fixtures: Begles/Bordeaux (h), Leinster (a), Leinster (h), Begles/Bordeaux (a).
Euro pedigree: Semi-finalists in their first campaign, 2000-01, they’ve managed just two quarter-finals in 13 since.
Formguide: Runs of first four wins and then three defeats, but bonus point win at home to Northampton last week put them fourth in the Premiership.
Key player: Santiago Carreras. As a converted winger, the Puma looked to the manor-born when tried there by Michael Cheika and last week he scored 19 points there for Gloucester, including a try and a gorgeous assist.
Odds: 100/1.
Prospects: Their potent maul and finishers ala Louis Rees-Zammit will make them a handful, particularly at Kingsholm.
NORTHAMPTON
Fixtures: La Rochelle (a), Munster (h), Munster (a), La Rochelle (h).
Euro pedigree: Champions in their first campaign in 2000 and beaten finalists in 2011, just three semi-finals in 10 efforts since.
Formguide: Sit sixth domestically despite winning just four from 10. They play some good stuff on that excellent Franklin’s Gardens surface but have leaked the most tries, 44, in the Premiership. Dan Biggar has been offloaded, leaving a void.
Key player: Alex Mitchell. He can strike from anywhere, witness 16 tries in his last 38 games – a high strike rate for a “9″.
Odds: 80/1.
Prospects: Their draw looks tough and they haven’t won away since April.
SALE SHARKS
Fixtures: Ulster (h), Toulouse (a), Toulouse (h), Ulster (a).
Euro pedigree: Two-time Challenge Cup winners in 2002 and 20‘05, three quarter-finals in 11 attempts in the Champions Cup.
Formguide: Second domestically with seven from nine and idle last week. As expected from a team coached by ex-Saracens forwards/defence coach Alex Sanderson, they’ve leaked the least tries in the Premiership under ex-Connacht assistant Mike Forahaw.
Key player: Any of the three du Preez brothers. The unrelenting back-row twins, Dan and Jean-Luc, lead the defence, while older brother Robert is the top points scorer in the Premiership.
Odds: 66/1.
Prospects: Have a tough draw but will be a tough nut to crack, particularly in winter in Salford.
