Caelan Doris
Club: Leinster
Position: Blindside flanker
Age: 24
Height: 6'4"
Weight: 107kgs (16st 9lbs)
Leinster appearances: 49
Points: 35
Why he's so important? In short because he is an outstanding rugby player with all the attributes to be one of the world's best. Ostensibly a number eight, Doris, who wins his 50th caps on Friday, has adapted well to the demands of blindside flanker and as a result it has allowed Leo Cullen to play both Doris and Jack Conan in the backrow. His game intelligence is striking on both sides of the ball, and it complements his athleticism, handling and footwork. The way he plays displays leadership and he's a future captain for club and country. The one area that might need a little refinement is his handling/passing.
Trivia: Born in the hamlet of Lacken, north Mayo, a few miles from the village of Killala, he was educated at the local primary school. There were two people in his class and 35 in total. He then headed to Blackrock College as a boarder. His dad Chris, who was educated there, was once the artist in residence with the Mayo County Council and spent 40 days and nights at the top of Croagh Patrick interviewing pilgrims as part of a 'social sculpture'. Caelan spent five years on a cup team between JCT and SCT and two years on the Ireland Under-20 side, one as captain.
Cian Prendergast
Club: Connacht
Position: Blindside flanker
Age: 22
Height: 6'5"
Weight: 112kgs (17st 9lbs)
Connacht appearances: 27
Points: 15
Why he's so important? There was no doubting his pedigree but even he might not have envisaged the impact he has made since joining Connacht from the Leinster academy. His form has not only earned him a regular place in Andy Friend's starting line-up – 17 appearances this season and counting – but was also recognised by Ireland coach Andy Farrell who called up Prendergast as a development player to the national squad. As befits someone who can also played secondrow he has a lineout presence but it his all-round game that makes him a strong contender for a plane ticket to New Zealand this summer.
Trivia: He only took up rugby when he went to secondary school at Newbridge College. At 15 years old he made the switch from backline, where he had played outhalf or centre to backrow at the suggestion of the senior thirds coach having undergone a "growth spurt". He recalled: "So I played a game there, played half decent, gave it a shot, and was called up to the first XV. I've played there ever since." An underage international where he came across Connacht coaches Cullie Tucker and Mossy Lawlor, he swapped the Leinster academy for an opportunity at Connacht last year and hasn't looked back since.