Llanelli look to be the best-placed club to surge into the quarter finals and a win against French giants Perpignan would provide a huge boost to the side currently top of the Welsh-Scottish league.
A win in France would blow the group wide open and set up a winner-takes-all showdown against Leicester next week at Stradey Park.
Judging from past seasons, the West Wales side have every reason to remain optimistic as they prepare to take on the French side.
Victories over Bourgoin and Colomiers prove the Scarlets have discovered the secret ingredient of winning on French soil.
Scott Quinnell will start the game from the bench having been ruled out for the last month with a knee injury, but is expected to play a part in the game.
Coach Gareth Jenkins said: "This is a big game for us and we know we have to win if we are to progress in the tournament.
"The secret to playing on French soil is not to try and play a running game because there is noone better than the French at that. What you have to do is try and silence the crowd which in turn will affect the team's temperament."
Meanwhile, Cardiff will be bidding to keep their Heineken Cup dreams alive with a morale boosting win over Montferrand at the Arms Park.
The Blue and Blacks have to win their two remaining games if they are to remain in contention for one of the best runner up spots.
The Welsh side will have received a boost with the news that Montferrand openside flanker Olivier Magne has been ruled out through injury.
Bridgend could do Cardiff a huge favour if they beat Castres at the Brewery Field on Saturday. A victory over the French club would increase Cardiff's chances of claiming one of the elusive runners-up positions.
Despite having lost all four games so far, the Ravens will be looking to end the group stages on a high note.
Newport will be hoping to keep alive their slim chances of clinching qualification when they lock horns with another French giant Toulouse.
Qualification for the last eight may be out of their hands following an agonising home defeat against Leinster, but Newport could still go through if they beat Toulouse and then Newcastle next week and other results are kind to them.
Swansea, who face Bath at St Helen's tomorrow, have delayed naming their side because of injury problems.
Wales lock Andy Moore has been ruled out with a neck strain while flanker Colin Charvis is doubtful.
The Whites have a mathematical chance of still qualifying but would have to run in five more tries than Bath following their 38-9 reverse at the Recreation Ground last October.
Welsh players and management joined Deputy Minister for Sport Ken Skates at the Pierhead Building, Cardiff Bay earlier this week to reveal the Union's pioneering school-club hub initiative has been so successful the project will now almost double the scale of the original project.
The Scarlets, Newport Gwent Dragons, Cardiff Blues and the Ospreys look ahead to Judgement Day III which sees the Blues take on the Ospreys (2.30) and the Dragons tackle the Scarlets (4.45pm) at the Millennium Stadium tomorrow afternoon.
Ystradgynlais and Ynysddu played out a titanic struggle at Taffs Well in the SSE SWALEC Bowl semi-final. At the end of the game neither team could be separated after a 15-15 stalemate but Ystradgynlais go through on try count.
Blues strike first in JD III battle - Newport Gwent Dragons lock Andrew Coombs, WRU referee Dylan Llyr Jones and Cardiff Blues hooker Matthew Rees decide dressing room allocations for Judgement Day III
Wales Under 18 captain Calum Haggett has received a conditional offer to read Biomedical Science at St Anne's College, Oxford. WRU chairman Gareth Davies went to meet Calum and Coleg y Cymoedd Principal Judith Evans to wish him luck in his exams and pass on some of his personal experience.
Dodgy tattoos, carthorses, Avatar and soft chins are revealed by Wales Sevens players Tom Williams and Sam Cross as they profile the Wales Sevens squad taking part in Hong Kong this weekend in the latest round of the HSBC Sevens World Series.