The European Rugby Champions Cup enters the semi-finals stage this weekend, with four worthy contenders left to contest for the title.
On Saturday, Leinster, who are favourites to win the competition, host Scarlets at the Aviva Stadium in Dublin.
Leo Cullen's side have been in outstanding form this season, both in Europe and in the Pro14, and went unbeaten in the group stage, recording two wins over each Montpellier, Exeter and Glasgow Warriors.
Leinster were at their flowing best in the 30-19 victory over reigning champions Saracens in the quarter-final earlier this month.
They have star quality throughout their entire side, including Jonny Sexton, who is widely regarded as the best fly-half in European rugby.
Leinster celebrate a try during their win over Saracens
The Dubliners have a ferocious pack up front, with Cian Healy, Sean Cronin and Tadhg Furlong in the front row supported by the likes of Dan Leavy, Sean O'Brien and Jordi Murphy.
Influential scrum-half Luke McGrath, who has formed a great half-back partnership with Sexton, could miss the game through injury, while Leinster will be hoping Ireland and Lions centre Robbie Henshaw is fit in time to join Garry Ringrose in midfield.
Scarlets finished top of Pool 5, which included French giants Toulon, Bath and Treviso.
The Welsh side have shown their creative brand of rugby on the domestic stage in recent seasons, picking up the Pro12 title last season, beating Leinster 27-15 in the semi-final before thrashing Munster 46-22.
They sit second in Conference B of the Pro14 this season, winning 13 of their 20 games, which would have been much higher if it weren't for the interruption of their squad from the Six Nations.
On the two occasions they've met this season, Leinster have recorded a 20-13 win at home, and a 10-10 draw in Wales.
Leinster's home form is notoriously superb, losing just two of their last 20 - one of which was a shock 17-15 defeat to Italian side Treviso, and the other the semi-final loss at the hands of the Scarlets.
Scarlets have only won one of the sides 13 previous meetings, and they will have to produce an exceptional performance on Saturday if they want to progress to the final.
On Sunday, Munster travel to take on French side Racing 92 at the Stade Chaban-Delmas.
Racing got to this stage after producing one of the best team performances of the entire Champions Cup in their 28-17 win over French rivals Clermont.
Racing 92 celebrate a try
They scraped into the quarter-finals after finishing second in Pool 4 - which was topped by semi-final opponents Munster.
In their two group meetings, each team recorded a victory, with Racing winning 34-30 at home, and losing 14-7 at Thomond Park.
Their home form is exceptional, losing just two of their last 20, including a 17-13 win over Toulon last time out.
They sit third in the French Top 14, winning 16 of their 24 fixtures, registering 541 points in the process.
Munster's route to the semi-final included four group stage wins, including two over Leicester Tigers, before a late 20-19 win over Toulon in the quarter-final.
Down by six points with only five minutes remaining, winger Andrew Conway produced a moment of brilliance to run in a try, which was converted by Ian Keatley.
Their main man is scrum-half Conor Murray, who over the past few years in his performances for club, country and the British & Irish Lions, has proved to be the best in the world in his position.
Munster also have game winners throughout their team, with CJ Stander and Peter O'Mahony in the forwards, and the likes of Keith Earls, Simon Zebo and Conway in the backs.
Andrew Conway scores a crucial try against Toulon
Racing are favourites to win the match given their formidable home form, but there is hope for Munster backers, as they won 32-7 at this very venue in last year's competition.
The two sides have met six times, with Munster winning on four occasions, but they will have to be at their very best form if they want to make that five, and produce an upset in France.
The two winners will contest the final on May 12th at the San Mames Stadium in Bilbao.
Words: Johnny Morton