Wales star Rhys Priestland believes the Scarlets will need to recreate intensity levels of their stunning victory over Northampton when they host European heavyweights Munster on Saturday.
Priestland and company have a shot at reaching the Heineken Cup quarter-finals after Pool One wins over Saints and Castres. Their bonus-point success at Franklin's Gardens, a triumph inspired by fly-half Priestland's tactical control, means back-to-back games with twice-tournament winners Munster over the next 10 days have taken on huge importance.
"Our young guys have no fear and we want to give it our best shot," Priestland said. "You need that against Munster, as you can get distracted by their pedigree."
He added: "We will show Munster a lot of respect, as they have earned it, and you have to respect guys like (Ronan) O'Gara, (Paul) O'Connell and (Donncha) O'Callaghan. But we need to back ourselves and go with the mentality to give it our best shot. It is going to take a performance of a similar standing to what we did in Northampton. We didn't create much ourselves, but we put the pressure on them."
Late O'Gara drop-goals edged Munster home against Northampton and Castres.
Conor O'Shea, meanwhile, has no doubt about the size of unbeaten Harlequins' task against French giants Toulouse on Friday.
Quins will bid for their 15th successive victory in all competitions this season, having won 10 Aviva Premiership games, two European ties and two Anglo-Welsh Cup fixtures. But Toulouse arrive at the Twickenham Stoop with an impeccable European pedigree after being crowned Heineken Cup winners four times and currently leading France's domestic championship.
"They set the benchmark for European rugby," Quins rugby director O'Shea said. "It is why we want to be in the Heineken Cup to play against teams like Toulouse. We always talk about testing ourselves to see where we stand, and we are playing against the best side in Europe."
Elsewhere, unbeaten Pool Two contenders Cardiff Blues and Edinburgh meet in Wales, while Ulster entertain Pool Four opponents Aironi at Ravenhill. Northampton head to Castres on Saturday without two suspended players - wing Chris Ashton and flanker Phil Dowson - which has increased their degree of difficulty in pursuing a first European win this season.
Like Saints, Gloucester have also lurched towards the last-chance saloon, knowing that defeat to Pool Six opponents Connacht in Galway would effectively mean elimination. Saracens, though, can keep themselves firmly among the quarter-final contenders from Pool Five by grounding Welsh challengers the Ospreys at Wembley, where Shane Williams is poised to make a first appearance since his emotional international career farewell last weekend.