Top ranking, home knockouts and final qualification spots are up for grabs as the EPCR Challenge Cup pool stages conclude.
With plenty on the line, expect fireworks in these final fixtures as sides push for as high a ranking as possible to secure home knockouts, while others scrap to continue their journeys.
As a reminder, the four highest-ranked clubs in each pool and the fifth-ranked clubs from each of the four Investec Champions Cup pools will qualify for the Round of 16.
All clubs will thereafter be ranked in descending order based firstly on their ranking in their pool and subsequently on the number of match points they have accumulated, to create an overall ranking from 1 to 16 - see more details here.
Find out where to watch all the action here, and make your score predictions here.
Friday: Cardiff and Connacht clash while Falcons face French foes Montpellier
Having beaten Lyon Olympique Universitaire with a bonus point in Round 3, Connacht Rugby secured a Round of 16 spot and will be aiming for the highest possible ranking for home knockouts thereafter as head to Cardiff Rugby.
The visitors travel to Galway needing a win to secure qualification, but a bonus point victory could put them in with a chance of a home knockout, which they'll have extra motivation for given the Final is being held just next door at the Principality Stadium in May.
At the same time, Montpellier Hérault Rugby heads to Newcastle Falcons having already qualified thanks to a bonus-point win over the Lions, so they will be hunting a high ranking.
Saturday: Four fateful fixtures
Section Paloise and Ospreys do battle to start a super Saturday - equal on 10 points in Pool 2 after both winning their Round 3 games against Dragons and Falcons respectively, they'll both be aiming for a high ranking to secure home knockout ties.
Pool 2 is then concluded as Lions host Dragons, also equal on points and both losing out in Round 3, in a head-to-head for the final qualification spots.
The last two games of the day follow that in the evening slot as Scarlets welcome RC Vannes and Toyota Cheetahs travel to Lyon.
Vannes are currently sitting in the last qualification spot in Pool 3 having earned a losing bonus point against Edinburgh Rugby, while Scarlets are a single point behind after coming away from Gloucester Rugby with nothing, so both need a win to secure knockout rugby.
Sunday: Three thrillers to tie up Pool Stages
A double header kicks off the final pool stage match day as Edinburgh host Black Lion and Gloucester travel to Aviron Bayonnais.
The Scots earned a bonus-point win on the road against Vannes in Round 3, but in a tight pool they still need a win to secure qualification and will be aiming for a home knockout, while the Georgians fell to Aviron Bayonnais and sit in the bottom spot needing a bonus-point win to confirm qualification.
Simultaneously, Gloucester head to France off the back of a bonus-point win over Scarlets and will be eyeing a home knockout spot, but will be going head to head for that space with Aviron Bayonnais on equal points after a bonus-point victory against Black Lion.
The pool stage concludes with Zebre Parma hosting USAP needing a bonus-point win and for Cheetahs to get nothing from their trip to Lyon in order to qualify, having lost all their games so far.
USAP, on the other hand, currently sit in fourth just three points off second, so will be aiming for a bonus-point win to boost any chances of a home knockout, while looking over their shoulder at Cheetahs who are level on points.