There is more than pride at stake
As the end of the regular season fast approaches, it's all change yet again at the top of the Pro12 table.
All five of the top teams have swapped places following last weekend's results, and with just four rounds left the scramble is on for a coveted play-off spot.
There are some tantalising games in store over the Easter weekend, from the Welsh double header at the Millennium Stadium to the interprovincial clash between Leinster and Ulster at the RDS.
The push for the play-offs kicks-off on Friday, when second placed Glasgow Warriors welcome Munster to Scotstoun Stadium.
A win at this stage is crucial for Munster who themselves are still chasing a top four finish; however Warriors have the prospect of a home play-off to encourage them.
The two Welsh Regions that are neck and neck for the fourth play-off spot are in action at the Millennium Stadium, but not against each other. Scarlets are first up on the double header bill when they take on Newport Gent Dragons, whilst Ospreys follow on with their game against Cardiff Blues.
There is more than pride at stake in these two fixtures, Ospreys and Scarlets have been swapping fourth and fifth spot in the table since round 13 and are currently only separated by points difference, so every point is critical in their final push for the play-offs.
Long time leaders Ulster, who have now dropped to third, are not in action until the last game of the round on Saturday, but that game is against the current table-toppers Leinster.
With just one point separating the two teams, victory for either side has the added bonus of denying the other, who are one of their main challengers for a home draw, the match points.
We look at all the Round 19 action!
Friday, March 29:
Zebre V Edinburgh
(Stadio XXV Aprile - Kick-off: 19.00; 18.00 GMT)
Zebre continue to search for that elusive first victory having claimed seven losing bonus points in the 18 rounds of the Pro12 played so far.
Edinburgh's unwanted eleven match losing streak was finally halted last weekend with their home win over Ulster.
Edinburgh's only two away victories this season came at Cardiff in round 2 and Connacht in round 10.
The Capital side have already tripped up against an Italian opponent this season going down 22-27 to Treviso at Murrayfield in October, but have not been defeated on a trip to Italy since they visited Aironi on 24th September 2011.
Edinburgh won 41-10 when the two sides met at Murrayfield in Round Three.
Zebre: 15 Paolo Buso, 14 Leonardo Sarto, 13 Giovanbattista Venditti, 12 Gonzalo Garcia, 11 Sinoti Sinoti, 10 Luciano Orquera, 9 Tito Tebaldi, 8 Andries van Schalkwyk, 7 Filippo Ferrarini, 6 Josh Sole, 5 Marco Bortolami, 4 Quintin Geldenhuys, 3 David Ryan, 2 Davide Giazzon, 1 Matias Aguero.
Replacements: 16 Andrea Manici, 17 Salvatore Perugini, 18 Luciano Leibson, 19 Michael van Vuuren, 20 Emiliano Caffini, 21 Alberto Chillon, 22 Samuele Pace, 23 Ruggero Trevisan.
Edinburgh: 15 Greig Tonks, 14 Lee Jones, 13 Matt Scott, 12 Ben Atiga, 11 Tim Visser, 10 Piers Francis, 9 Greig Laidlaw (captain), 8 Netani Talei, 7 Ross Rennie, 6 Stuart McInally, 5 Sean Cox, 4 Perry Parker, 3 Willem Nel, 2 Ross Ford, 1 Allan Jacobsen.
Replacements: 16 Steven Lawrie, 17 John Yapp, 18 Geoff Cross, 19 Robert McAlpine, 20 Hamish Watson, 21 Sean Kennedy, 22 Harry Leonard, 23 Tom Brown.
Referee: Sean Gallagher (Ireland)
Assistant Referees: Stefano Traversi, Filippo Bertelli (both Italy)
TMO: Alan Falzone (Italy)
Glasgow Warriors v Munster
(Scotstoun Stadium - Kick-off: 20.05; 20.05 GMT)
Glasgow Warriors' record seven game winning run in the Pro12 came to an end in Dublin on Saturday.
Warriors have won their last five matches in all competitions at Scotstoun since losing there, 6-9, to Castres in the European Cup in December.
Glasgow's only win in their last six encounters with Irish provinces was 20-14 at home to Ulster in round 16.
Munster ended a three game winless run in the Pro12 with their victory over Connacht in Cork last weekend.
The Munstermen have not won outside of Ireland in the Pro12 since a trip to Cardiff Blues on 2 November.
Munster's only defeat in their last 15 contests with Scottish opponents in all competitions since 2009 was to Edinburgh at Murrayfield in September 2011.
Munster have won the last six fixtures against Glasgow since the Warriors last win, 22-9, at Firhill in the opening game of the 2009/10 campaign.
Glasgow Warriors: 15 Stuart Hogg, 14 Sean Maitland, 13 Sean Lamont, 12 Peter Horne, 11 DTH van der Merwe, 10 Ruaridh Jackson, 9 Niko Matawalu, 8 Ryan Wilson, 7 John Barclay, 6 Josh Strauss, 5 Al Kellock (captain), 4 Tim Swinson, 3 Jon Welsh, 2 Pat MacArthur, 1 Ryan Grant.
Replacements: 16 Mark Bennett, 17 Duncan Weir, 18 Henry Pyrgos, 19 Rob Harley, 20 Tom Ryder, 21 Moray Low, 22 Dougie Hall, 23 Ofa Fainga'anuku.
Munster: 15 Felix Jones, 14 Doug Howlett (captain), 13 Casey Laulala, 12 James Downey, 11 Johne Murphy, 10 Ronan O'Gara, 9 Duncan Williams, 8 James Coughlan. 7 Tommy O'Donnell, 6 Paddy Butler, 5 Paul O'Connell, 4 Donncha O'Callaghan, 3 BJ Botha, 2 Mike Sherry, 1 David Kilcoyne.
Replacements: 16 Damien Varley, 17 Wian du Preez, 18 Stephen Archer, 19 Billy Holland, 20 Niall Ronan, 21 Cathal Sheridan, 22 Ian Keatley, 23 Ivan Dineen.
Referee: Leighton Hodges (Wales)
Assistant Referees: Peter Allan, Adrian Graves (both Scotland)
TMO: Iain Ramage (Scotland)
Saturday, March 30
Newport Gwent Dragons v Scarlets
(Millennium Stadium - Kick-off: 14.30; 14.30 GMT)
Newport Gwent Dragons' only two wins in the Pro12 since round 9 have both been against Italian opponents.
Dragons have lost their last six encounters with fellow Welsh regions in the Pro12 since beating Cardiff Blues at Rodney Parade 15 March 2012.
This will be Dragons first ever visit to the Millennium Stadium.
Scarlets solo defeat in their last six matches in all competitions was 5-32 to Leinster at the RDS on 23 February.
Scarlets have lost just two of their last thirteen contests with fellow Welsh regions in all tournaments.
Scarlets only previous visit to the Millennium Stadium came on 4 March 2006 in the semi-final of the Anglo-Welsh Cup, beating Bath there 27-26. Scarlets have won the last nine encounters between the two teams in the Pro12.
Newport Gwent Dragons: 15 Tom Prydie, 14 Will Harries, 13 Pat Leach, 12 Jack Dixon, 11 Ross Wardle, 10 Dan Evans, 9 Jonathan Evans, 8 Toby Faletau, 7 Nic Cudd, 6 Dan Lydiate, 5 Rob Sidoli, 4 Andrew Coombs (captain), 3 Dan Way, 2 Hugh Gustafson, 1 Aaron Coundley.
Replacements: 16 Sam Parry, 17 Owen Evans, 18 Nathan Buck, 19 Jevon Groves, 20 Ieuan Jones, 21 Wayne Evans, 22 Steffan Jones, 23 Adam Hughes.
Scarlets: 15 Gareth Owen, 14 George North, 13 Jonathan Davies, 12 Scott Williams, 11 Liam Williams, 10 Owen Williams, 9 Aled Davies, 8 Rob McCusker (captain) 7 Johnathan Edwards, 6 Aaron Shingler, 5 Johan Snyman, 4 George Earle, 3 Samson Lee, 2 Matthew Rees, 1 Phil John.
Replacements: 16 Ken Owens, 17 Rhodri Jones, 18 Deacon Manu, 19 Sione Timani, 20 Josh Turnbull, 21 Rhodri Williams, 22 Aled Thomas, 23 Gareth Maule.
Referee: Neil Paterson (Scotland, 49th competition game)
Assistant Referees: Neil Hennessy, Jon Mason (both Wales)
Cardiff Blues v Ospreys
(Millennium Stadium - Kick-off: 17.15; 17.15 GMT)
Cardiff Blues have slipped to three straight defeats in the Pro12 since their 17-16 victory against Edinburgh at Murrayfield 15th February.
The Blues are unbeaten in their last three matches at the Millennium Stadium, which were all the in European Cup, and won 40-31 against Leinster on their only previous encounter there in the Pro12, in May 2006.
The Blues only two wins in their last nine contests with fellow Welsh regions in the competition have both been against Newport Gwent Dragons.
Ospreys' sole defeat in their last nine Pro12 matches since November was 10-22 to Connacht in Galway in Round 15. Ospreys only two previous visits to the Millennium Stadium were both semi-final encounters in the Anglo-Welsh Cup, in 2007 and 2008, winning them both, against Cardiff Blues and Saracens respectively.
Ospreys have won their last seven clashes with fellow Welsh regions in the Pro12.
Cardiff Blues have not beaten Ospreys since a 27-25 victory at the City Stadium on New Year's Eve 2010.
Cardiff Blues: 15 Leigh Halfpenny, 14 Owen Williams, 13 Gavin Evans (c), 12 Dafydd Hewitt,11 Harry Robinson, 10 Rhys Patchell, 9 Lloyd Williams, 8 Luke Hamilton, 7 Sam Warburton, 6 Michael Paterson, 5 Lou Reed, 4 Filo Paulo , 3 Scott Andrews, 2 Marc Breeze, 1 Sam Hobbs.
Replacements: 16 Kristian Dacey, 17 Thomas Davies, 18 Taufa'ao Filise, 19 Robin Copeland, 20 Rory Watts-Jones, 21 Lewis Jones ,22 Ceri Sweeney, 23 Gareth Davies.
Ospreys: 15 Richard Fussell, 14 Tom Habberfield, 13 Jonathan Spratt, 12 Ashley Beck, 11 Tom Isaacs, 10 Dan Biggar, 9 Kahn Fotuali'i, 8 Jonathan Thomas, 7 Justin Tipuric, 6 James King, 5 Ian Evans, 4 Alun Wyn Jones (captain), 3 Adam Jones, 2 Richard Hibbard, 1 Ryan Bevington
Replacements: 16 Scott Baldwin, 17 Duncan Jones, 18 Dmitri Arhip, 19 Lloyd Peers, 20 Joe Bearman, 21 Rhys Webb, 22 Matthew Morgan, 23 Ben John.
Referee: Nigel Owens (Wales)
Assistant Referees: Ian Davies, Sean Brickell (both Wales)
TMO: Nigel Whitehouse (Wales)
Leinster v Ulster
(RDS Dublin - Kick-off: 18.15; 18.15 GMT)
Leinster are the best side in the Pro12 on current form having won their last seven matches since Ulster beat them in Belfast in December.
The Leinstermen moved to the top of the Pro12 table for the first time this season following their 22-17 win against the then top of the table Glasgow Warriors last weekend.
Leinster's only home defeat to a fellow Irish province since 2003 in the Pro12 was to Munster at the RDS in September 2008.
Ulster are winless in their last three Pro12 matches and have picked up just four league points along the way.
The Ulstermen have lost their last three away games in the competition since beating Scarlets in Llanelli in early December.
The Ulstermen have not beaten a fellow Irish province on their own soil in the Pro12 since a trip to Connacht in September 2009.
Ulster's 27-19 victory over Leinster in Belfast in round 11 ended a run of seven straight defeats to the Leinstermen in all competitions, however Ulster have not beaten Leinster in Dublin since August 1999, in the Interprovincial Championship at Donny brook
Referee: George Clancy (Ireland)
Assistant Referees: Leo Colgan, David Connolly (both Ireland)
TMO: Jude Quinn (Ireland)
Benetton Treviso v Connacht
(Stadio Monigo - Kick-off: 20.00; 19.00 GMT)
Benetton Treviso are unbeaten in their last three Pro12 fixtures and are on target to produce a best ever finish in the competition.
Treviso have won their last four games in the Pro12 at the Stadio Monigo, their best ever home run.
The Italians are also unbeaten in their last two games against Irish opponents.
Connacht's three game winning run in the Pro12 ended at the hands of Munster in Cork last weekend.
Connacht's only two away victories in the competition this season came against Zebre in Round Two and Cardiff Blues in Round 16.
The Irishmen have won their last six matches against Italian opponents in all competitions.
Connacht have the slight edge in encounters between the two teams winning three to Treviso's two, and were victorious 18-3 when Benetton visited Galway in round 8.
Benetton Treviso: TBC
Referee: Andrew McMenemy (Scotland)
Assistant Referees: Elia Rizzo, Filippo Navarra (both Italy)
TMO: Mauro Dordolo (Italy)