British & Irish Lion Lawrence Dallaglio is preparing for his toughest challenge of the season when Wasps open their European Cup campaign against Edinburgh at Murrayfield on Sunday.
Dallaglio, who is two matches into his comeback after a broken ankle, faces Lions colleague and Scotland number eight Simon Taylor.
Both men have points to prove after their respective Lions tours were ruined by injury.
Dallaglio played 17 minutes before breaking his ankle against Bay of Plenty while Taylor never even made it onto the field after being struck down in training by a hamstring injury.
Now both are back on the field and with international ambitions burning brightly, Dallaglio is looking forward to a fierce encounter.
"Simon is a very talented player but his career has been severely hampered by a horrible run of injuries," he said.
"He is back to full fitness and has performed well in the last three games for the Gunners, and I am pleased with the progress that I have made since coming back from my injury.
"I felt much better in the game against Sale last Friday, despite the result. But I will need to raise my levels again for this one - Simon is one of the best number eights around."
Wasps are without Fraser Waters, who has been struck down again by the ankle injury which kept him out all last season, while flanker Joe Worsley has a knee ligament problem.
With Ayoola Erinle also out, Josh Lewsey continues at outside-centre while John Hart comes into the back row for Worsley.
Boss Ian McGeechan said: "We are a little unsettled due to injuries and face an Edinburgh team in form - they have lost only once at home since Christmas 2004."
The Gunners, third in the Celtic League, have included Australia international Peter Jorgensen in the centre and boss Todd Blackadder has laid down a challenge to his men.
"They have been champions in the English Premiership for the last few years in a row and are undoubtedly one of the top sides in Europe," said Blackadder.
"At first glance you would think there are very few chinks in their armour but we have nothing to lose. We are aiming to play some rugby and take the game to them."
French powerhouse Stade Francais, fresh from beating Toulouse in front of 80,000 in Paris last weekend, travel to south Wales to take on the Ospreys without international quartet Agustin Pichot, Christophe Dominici, Sylvain Marconnet and David Auradou.
The Ospreys are missing Gavin Henson and Ryan Jones but Sonny Parker is back in the side and head coach Lyn Jones said: "The team is excited about hosting one of the best teams in European rugby, and the players are motivated to do themselves justice in our performance. If we can realise our true potential it will be a fantastic contest."
Saracens return to the European Cup for the first time in five years and face a huge test with French champions Biarritz travelling to Vicarage Road.
"We know they have a very dangerous side as they have shown in the competition for the last few years - not to mention winning the French title last year," said Kevin Sorrell.
Biarritz are brimming with France internationals, with Nicolas Brusque, Damien Traille, Dimitri Yachvili, Imanol Harinordoquy, Jerome Thion and Thomas Lievremont in the side.