Two of the oldest names in European rugby compete for the first time when Cammi Rugby Calvisano face Agen at Centro Sportivo San Michelle.
Calvisano will be eager to make a winning return after a three-year absence from European competition.
Much will depend upon the experience of their half-backs, former Italy pair Paul Griffen and fly-half Andrea Marcato who have remained faithful to the former Italian champions.
Agen once regularly reached the knock-out stages of Europe but not have done so since 2005, the same year they suffered their only defeat to Italian opposition, Viadana, in 12 encounters.
France great Phillipe Sella is among a knowledgable coaching staff that has helped Agen recover from a shaky start to win three of their last four games in Top 14.
Ex-Wales centre Jamie Robinson provides guile in midfield while South African fly-half Conrad Barnard already needs just one more score to hit 100 points this season.
