Ulster have scored just nine tries in five games, compared with Llanelli (22), Castres (17) and Cardiff (16), the others chasing a best runner up spot.
Good news for Ulster is that David Humphreys, who retired injured against Wasps, passed a fitness test yesterday afternoon and was confirmed in the team.
Humphreys scored a tournament record 37 against Wasps at Ravenhill but tonight will be required to get his backline moving and with that in mind coach Alan Solomons has promoted Australian Ryan Constable to the centre at the expense of Adam Larkin.
Simon Mason returns to Ravenhill with the Italian side who he joined this season after a stint with Stade Franca and he is the tournament leading scorer with 83 points. His side include 14 internationals (centre Stewart Magorian is the only non-capped player) that includes players of the calibre of the Dallan brothers, Manuel and Denis, hooker Alessandro Moscardi, flanker Mauro Bergamasco and number eight Carlo Checchinato and they will not readily lie down to oblige Ulster. When the sides met in the competition earlier on Ulster won 33-28.