Carlow's Sean O'Brien will win his 100th Leinster cap in the New Year's Day clash with Connacht at the Sportsground should be come off the bench. But he won't be the only Sean O'Brien wearing the no. 20 jersey, after Pat Lam named 21-year-old Galway-born Sean O'Brien on his replacement's bench for the clash.
Both teams welcome back some faces from injury, with Connacht making three changes, and Leinster changing 12. Pat Lam's side are boosted by the return of openside flanker Jake Heenan, as well as New Zealander Tom McCartney to the starting XV. Andrew Browne comes into the second row in the only other change to the side, who will have Matt Healy on the wing having just signed a two-year extension to stay out West. Heenan's return from injury is particularly noteworthy with his horrendous injury history, and Connacht's win percentage with the New Zealander in the team is significantly higher than without.
Leinster welcome back Johnny Sexton, Luke McGrath, Ben Te'o to the lineup. Te'o partners Garry Ringrose in an exciting centre-partnership. Rhys Ruddock captains an otherwise youthful looking team - partnered in the back-row by Josh van der Flier, and Jordi Murphy.
Connacht: T O'Halloran, N Adeolokun, B Aki, C Ronaldson, M Healy, J Carty, K Marmion; F Bealham, T McCartney, N White, A Muldowney, A Browne, J Muldoon (capt), J Heenan, E Masterson
Replacements: D Heffernan, R Loughney, R Ah You, U Dillane, S O'Brien, I Porter, AJ MacGinty, R Parata
Leinster: R Kearney, F McFadden, G Ringrose, B Te'o, D Kearney, J Sexton, L McGrath; J McGrath, R Strauss, M Moore, D Toner, M McCarthy, R Ruddock (capt), J van der Flier, J Murphy
Replacements: J Tracy, P Dooley, M Bent, R Molony, S O'Brien, E Reddan, I Madigan, Z Kirchner
Munster and Ulster have both named their teams for Saturday's clash in Kingspan Ravenhill stadium. Ulster have named a strong team, and while there are several changes from the team that narrowly beat Connacht, Kiss makes just three changes from the team that won in Toulouse in the Champions Cup. Two of those moves are injury-related, with Rory Scholes replacing Craig Gilroy like he did ten minutes into that game, and Chris Henry returns in place of Sean Reidy.
Munster head coach Anthony Foley has made seven changes to the side in an attempt to halt their losing streak. Ronan O'Mahony and Lucas Amorosino come into the team in place of Keith Earls and Simon Zebo on the wings, while Ian Keatley returns to the side in place of Tyler Bleyendaal. In the pack, the injury to James Cronin sees him replaced with Dave Kilcoyne, whilst Mark Chisholm and BJ Both come in for Donnacha Ryan and John Ryan. It's a strong backrow with Tommy O'Donnell's first start back - Jack O'Donoghue switches to blindside with CJ Stander captaining from No. 8.
Ulster: L Ludik, A Trimble, L Marshall, S McCloskey, R Scholes, P Jackson, R Pienaar; K McCall, R Best (capt), W Herbst, L Stevenson, F van der Merwe, R Diack, C Henry, N Williams.
Replacements: R Herring, C Black, R Lutton, A O'Connor, R Wilson, P Marshall, I Humphreys, S Arnold.
Munster: A Conway; R O'Mahony, F Saili, R Scannell, L Gonzalez Amorosino; Ian Keatley, Tomás O'Leary; Dave Kilcoyne, Mike Sherry, BJ Botha; Dave Foley, Mark Chisholm; Jack O'Donoghue, Tommy O'Donnell, CJ Stander (capt).
Replacements: Niall Scannell, John Ryan, Mario Sagario, Billy Holland, Robin Copeland, Duncan Williams, Tyler Bleyendaal, Denis Hurley.
Picture credit: SPORTSFILE
