They are a point clear at the top of the table and travel the short distance to St Helens, Swansea, for a Sunday showdown with the Neath-Swansea Ospreys that could decide if they can break the Irish monopoly on the title.
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Leinster Lions and Munster have made sure the crown has stayed firmly in Ireland so far but now both the Scarlets and The Dragons are chasing a Welsh "first."
However, The Scarlets have to put what coach Nigel Davies calls "a terrible performance, we were not happy with it at all and we did not impose ourselves in any shape or form" against Glasgow Rugby behind them and prepare for a fierce local derby against a side still battling to qualify for next season's Heineken Cup.
"It is a huge game - both teams are desperate for the win, albeit for different reasons," he said. "The Ospreys are the form team in the Celtic League at the moment - the stats don't lie - and it is going to be very interesting at St Helens.
"Both sides know that a local derby like this comes down to who wants it the most on the day - and, as if any extra edge were needed, that is what could decide the game."
Sean Holley, the Ospreys' assistant coach, said: 'The players are really looking forward to this match.
"The whole squad wants to play against the best, and The Scarlets are clearly the best side in Wales at the moment.
"Being the best in Europe means that you must first be the best side in Wales and that means that you must show yourself to be able to beat The Scarlets.
"The players enjoyed playing in front of a huge Stradey Park crowd in our last fixture, and it would be nice if we could return the compliment at St Helens at the weekend.
"It is a huge game for both sets of supporters as The Scarlets are pushing for the title, and we are still competing to secure the final Heineken Cup place.
"We enjoyed a great atmosphere against The Blues last time out at St Helens, in a match also played on a Sunday afternoon, and I hope that will again be the case this Sunday.
'We were pleased with our defence in Leinster, but our attacking game had too many mistakes and was not up to our usual standard.
"We will focus our efforts on executing our possession this week in training.
"We have had problems with injury and availability throughout the season, but are now fortunate to be picking from a full strength squad at a crucial time in the season.'