Llanelli were the only side to gain maximum points when they beat Glasgow 45-15 at Stradey Park.
Neath did manage a draw with Heineken Cup champions Leicester Tigers, but Cardiff, Swansea and Newport all suffered morale-denting defeats.
Fans of the three teams will be desperate for maximum points - but reversals for Newport and Swansea will increase the already growing pressure on coaches Richard Hill and Leigh Jones (Newport) and Jon Connolly. (Swansea)
Dai Young and his Cardiff side have the unenviable task of travelling to Ireland to play Ulster this evening.
The Irishmen will be reeling after last weekend's 32-9 loss at the hands of 2000 Heineken Cup champions the Northampton Saints. After a good start to the season in the Celtic League, that defeat will have hurt Ulster Branch, and they will be planning a comeback with a strong performance against the Blue and Blacks.
Cardiff have made four changes to the side that lost against Biarritz Olympique with under-fire prop Peter Rogers being dropped from the squad altogether.
Newport will need confidence to beat Toulouse and claim their first win since May. The Black and Ambers have lost 10 straight games since Hill and Jones took the helm.
Matt Pini, Andrew Powell and Steve Ojomoh all come into the side in this must win game.
Toulouse have lost forwards David Gerard and Jean Bouilhou and their absence needs to be exploited by the Black and Ambers pack if victory is to be achieved.
Things could go from bad to worse for Swansea coach John Connolly when his side host Leinster on Saturday.
The Irish side opened their European account in the perfect way, beating Bristol 29-23. But Swansea put in yet another dour performance losing to Montferrand 47-12.
Leinster are one of the favourites for Heineken Cup glory this season and their star-studded squad should secure victory against a Swansea side reeling from recent defeats.
Neath will be without scrum-half Andy Moore for their trip to Bezier. Lyn Jones' men performed well last week with the experienced Moore pulling the strings, and his absence mean ex club captain Patrick Horgan starts.
Neath will be looking to build on their impressive draw with Leicester last Friday, but Beziers got off to a winning start last weekend and will certainly cause the Welsh All Blacks problems at the Stade de la Mediterranee.
Llanelli face Bourgoin on Friday night. Bourgoin will be full of confidence following their 24-18 victory over PARKER PEN SHIELD holders Sale Sharks last weekend.
The Scarlets have made slight alterations to the side that beat Glasgow, with Dafydd Jones replacing Ian Boobyer and David Hodges replacing Simon Easterby in the backrow.
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