If you take the law of averages, only one away side a year prevails at the Champions Cup quarter-final stage – a statistic that this year’s four English teams will be only too aware of.  In the past, many highly-regarded outfits have withered in the face of partisan home support. So, if history is to repeat itself, which lone side will triumph in spite of the odds heaped against them? Below are eight key clashes to watch out for in this year’s quarter-finals.

Leinster v Bath (KO 15.15, Saturday)

Sean O’Brien v Francois Louw

Although not the classic ‘fetcher,’ the magnitude of Sean O’Brien’s influence in the loose cannot be downplayed. The Irishman was man-of-the-match in his country’s last Six Nations game. Against Scotland he was titanic, beating seven defenders on his way to a try-brace, tries that determined the championship.

Leinster are narrow favourites but if Bath are to succeed Francois Louw must continue to dominate breakdown play in order to feed an electrifying backline. Bath’s flanker remains one of the most effective on the deck in world rugby, contributing six turnovers so far this tournament, including a crucial steal in the dying minutes against Glasgow. It will be some battle.

Louw rider: Francois Louw is good on the deck and a testing adversary for Sean O’Brien

Jimmy Gopperth v George Ford

George Ford’s playmaking ability on the fringes of the gainline could prove the decisive factor, if given the space. The English fly-half will look to unleash the dangerous trio of Kyle Eastmond, Jonathan Joseph and Anthony Watson that left the Toulouse chasing vapour trails.

Jimmy Gopperth will take confidence from Ireland’s shackling of Ford in the Six Nations where, through a combination of tactical kicking and aggressive pressing, Joe Schmidt‘s side starved the Bath No. 10 of high-quality possession. The New Zealander, who departs for Wasps in the summer, is also a threat with ball in hand and will seize on any opportunity to run down the 10 channel to pressure his opposite number.

Clermont v Northampton (KO 17.45, Saturday)

Fritz Lee v Samu Manoa

Northampton will need a performance equal in precision and brutality if they are to win away at the graveyard of ambition; the Stade Marcel Michelin. The mountainous Samu Manoa will play a crucial role in proceedings. Manoa’s power permeates from every facet of his game.

Along with fellow enforcer Courtney Lawes, they will need to be at their chiropractic best if they are to disrupt Clermont’s rhythm and end a twenty-two-game unbeaten streak at home. Saints, however, will have to circumnavigate around No 8 Fritz Lee. The Samoan is one of the most dynamic carriers in the tournament, possesses deft handling skills and has contributed 62 tackles already this tournament – more than any other Clermont player.

Skittles: Samu Manoa will take some stopping but Fritz Lee will bring his own danger

Noa Nakaitaci v Ken Pisi

With George North sidelined, it say something of Northampton’s strength-in-depth that they can call upon on another strike runner in devastating form. Ken Pisi‘s recent performances are underlined by an enviable set of statistics placing him in the top ten of every attacking facet of the tournament: 11 clean breaks (2nd in the tournament), 449 metres gained (4th in the tournament), 19 defenders beaten (5th in the tournament), 10 offloads (8th in the tournament).

His opposite number, Noa Nakaitaci, has made a respectable 377 metres himself (7th in the tournament) and he proved to be one of the few shining lights in a blunted French back line during this year’s Six Nations.

Racing Metro v Saracens (12.45, Sunday)

Jamie Roberts v Chris Wyles

Chris Wyles produced an impressive performance in his last outing dotting down twice and setting up Chris Ashton. The veteran American, however, will face an altogether different proposition when he faces Europe’s in-form No 12 – Jamie Roberts.

The Welshman remains the fulcrum of attack for both his national and club side with his ability to breach the gain line, time after time. Stopping Roberts is one of the keys to victory in Paris with Saracens needing no less than defensive perfection to yoke the cerebral Welsh Juggernaut.

Finishing act: Racing’s Teddy Thomas is a danger man out on the flank

Teddy Thomas v Chris Ashton

At the grand old age of 28, Chris Ashton seems to be having a renaissance. The Englishman scored twice in front of a world record crowd at Wembley and leads the club’s scoring charts in Europe with four tries. Indeed, many are calling for his reinstatement to the national side.

Although Ashton’s opponent has not struck the same rich vein of form with one try in this year’s tournament, Teddy Thomas‘ boundless athleticism, power and natural finishing ability will certainly trouble the league convert. Thomas is also gifted with an exquisite side-step that can leave the most redoubtable defender flailing.

Toulon v Wasps

Steffon Armitage v James Haskell (KO 15.15, Sunday)

While the debate on his selection will continue up until, and probably after, the World Cup there is no question of Steffon Armitage significance to his club side. The versatile back-row forward has already scored four tries this season carrying the ball 72 times (6th highest in the tournament) in the process. James Haskell will provide a muscular adversary for the European Player of the Year. The Wasps’ captain enjoyed a solid Six Nations guarding England’s blindside and will aim to choke the life out of the opposition. If he is to stop Armitage and Toulon, fans should hope for a repeat of the flanker’s performance against Wales.

Access all areas: Steffon Armitage’s ball carrying means James Haskell will have his work cut out

Mathieu Bastareaud v Elliot Daley

Elliot Daley appears anything but disheartened by his omission from Stuart Lancaster’s Six Nation squad, scoring four tries in his last five appearances. His frenetic style is the antithesis to Mathieu Bastareaud‘s rumbling route-one lines of attack, although he boast a better offloading game than many give him credit. While the 22-year-old seems to be in the ascendancy, it is Bastareaud’s star that seems to be receding with the Frenchman rightly dropped by Philippe Saint-Andre. Yet Bastareaud’s remains a presence in Europe with three tries in his last three appearances and the tournament favourites will seek his hulking frame to batter large fissures in the Wasp’s midfield.