With just seven rounds left in the RaboDirect PRO12, the race is on for the prized top four finishing places and qualification for the play-off semi-finals.
As one of the top billing fixtures of the weekend, the Scarlets sit in fourth after a big win against Munster last weekend on home soil and now have 46 points - just three short of Leinster in third.
After winning their last three games in a row at Parc y Scarlets, it's a big chance for the Scarlets to build on the positive momentum of the last three weeks and make a jump ahead of Leinster and take third place in the race.
The West Wales side know it will be a tall order, given Leinster's impressive form at home as the Irish province remain the only side in the RaboDirect PRO12 to be unbeaten at home this season.
Leinster have won their last six matches in all competitions and remain the only side with a 100% winning record at home in the RaboDirect PRO12 this season.
Scarlets are back on the road this weekend after have won their last three games in all competitions at home. The Scarlets meet Leinster for the fourth time this season having played them in both the league and Heineken Cup.
The Scarlets only victory over Leinster in their last 10 meetings in all competitions was 45-20 at Parc y Scarlets in the opening game of this season on September 1st.
Head Coach Simon Easterby said: "We have to go back to October 2007 to find the last time we won at the RDS, so we know we have plenty to do out there. Leinster have a very proud home record and we know from our encounters in Europe what intensity they can bring.
"We got a good win against them at the beginning of the season and that gives us heart; however we're also well aware that we caught them a bit cold that day and you won't see that in a Leinster team too often.
"We have learnt a lot from our performances in December and January and particularly our games against them in the Heineken Cup; we know that any mistakes from us will be capitalised on. They are a well-coached and well-drilled team."
Easterby said that the sides may both be missing international players but with the stakes so high in the remaining seven league games, the visitors would not underestimate the intensity and physicality of the game ahead of them.
The Scarlets Head Coach said he felt his side had turned a corner in recent weeks: "We are pleased with the form we have coming into this game, it will be tough but the boys have responded well and with some continuity in selection now, we are building.
"Winning against Munster last weekend, we showed there was less error in our game, we're not feeding the opposition and starting to reward ourselves more with good territory and field possession.
"We have put pressure on sides by taking our points from goal kicking and drop goals and rewarding our forwards for their efforts by keeping the scoreboard ticking over."
In the forwards, Wales international Aaron Shingler returns to his region to take his place in the back row alongside captain Rob McCusker and Kieran Murphy at no 8.
Outside half Aled Thomas moves to full back for the injured Gareth Owen and Easterby keeps faith in his young nine and 10 combination with Aled Davies winning the starting scrum-half contest alongside man of the match from last weekend Owen Williams who scored 18 points with the boot last weekend.
Outside half Williams who celebrates his 21st birthday on Wednesday next week (27/02) plays in his 8th game for the region with a points haul of 74 already this season.
Easterby said the play-off battles really added a healthy focus to the Celtic league competition during the Six Nations contest.
"It's great to have this kind of intensity building in these games now - teams know that during this period they can rule themselves out of contention fairly quickly to it keeps a sharp focus. It is a really good addition to the competition to have top four play offs."
The Scarlets Head Coach praised his back room team for working hard to keep injury levels low for this period in the season and allowing the coaching set-up to build depth in some key positions.
"We are fortunate at the moment to have a low injury rate and the medical and strength and conditioning teams are doing excellent work behind the scenes to keep the players healthy and match fit which is key when you have lost so many players not only to the national squad but to the Wales U20's and 7's as well."
Scarlets team v Leinster, Saturday 23rd February kick off 7.45pm RDS; 15 Aled Thomas, 14 Nick Reynolds, 13 Gareth Maule, 12 Adam Warren, 11 Andy Fenby, 10 Owen Williams, 9 Aled Davies, 1 Phil John, 2 Emyr Phillips, 3 Jacobie Adriaanse, 4 George Earle, 5 Johan Synman, 6 Aaron Shingler, 7 Josh Turnbull, 8 Rob McCusker (capt).
Replacements: Matthew Rees, Rhodri Jones, Samson Lee, Jake Ball, Sione Timani, Gareth Davies, Kristian Phillips, Dale Ford.
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