The Magners League attendance record looks set to be shattered when Leinster and Munster go head-to-head at Lansdowne Road (7.30pm) on Friday.
At present some 14,000 tickets have been sold and officials remain hopeful of a crowd somewhere in the region of 20,000.
The previous best attendance in the competition was 15,327 when Leinster travelled to the Cardiff Blues in May.
The West Lower stand is now completely sold out while there are only a few hundred seats available in the East Lower. Due to demand the East Upper will now be opened.
Leinster coach Michael Cheika today named his squad and Rob Kearney, Cameron Jowitt and Brian Blaney are all included having missed the win over Connacht last weekend.
"Rob Kearney returns to the squad after missing the last game with a slight hamstring injury. That will make it (selection) tight going in the backline," said Cheika today.
Brian O'Driscoll will captain the side which will be named tomorrow.
Cheika is looking forward to renewing what he describes as a "brilliant" rivalry and is keen to even the score.
"We've won one and lost two against them since I've arrived so you're always looking to level the score! It's a brilliant fixture and the rivalry, build-up and hype is great," said the Australian.
"We've learned our lesson from the last game with them and the fact remains that we're a different team - and they are too.
"I thought Munster played very well against Ulster the other night. They're a quality outfit. Their two half-backs are excellent match managers and Alan Quinlan is an added player that we didn't face last year who is an outstanding counter-rucker."
Shaun Payne and Ian Dowling are both included in the Munster squad. Barry Murphy also returns for the first time since sustaining injury against Ulster last season.
Christian Cullen and Anthony Horgan have had scans on the injuries they picked up against Ulster last Saturday.
Horgan has damaged cartilage and will see a specialist later in the week while Cullen's results proved inconclusive and he must have another scan.
Michael Bradley has also named his Connacht squad to face Ulster at the Sportsground on Friday (6.30pm).
The Connacht coach was forced to plan without the injured sextet of Conor O'Loughlin, Ronan Loughney, Joe Merrigan, David McGowan, Conor McPhillips and Stephen Knoop.
Ulster will name their team at 12 noon tomorrow.
Leinster: R Corrigan, B Jackman, W Green, H Vermaas, B Blaney, R McCormack, M O'Kelly, T Hogan, O Finegan, S Keogh, K Gleeson, J Heaslip, C Jowitt, N Ronan. C Whitaker, G Easterby, C Warner, F Contepomi, G D'Arcy, B O'Driscoll (capt), S Horgan, D Hickie, L Fitzgerald, G Dempsey, R Kearney.
Munster: J Kelly, S Payne, I Dowling, T Halstead, R O'Gara, P Stringer, T O'Leary, B Murphy, J Manning, B O'Meara, E Hickey, M Horan, A Kyriacou, F Pucciariello, F Roche, F Sheahan, D O'Callaghan, P O'Connell (capt), A Quinlan, D Wallace, A Foley, T McGann, T Ryan, M O'Driscoll.
Connacht: Andrew Farley, Adrian Flavin, John Fogarty, David Gannon, Ray Hogan, Chris Keane, Matt Lacey, Keith Matthews, Mark McHugh, Matt Mostyn, John Muldoon, Ray Ofisa, Colm Rigney, Daniel Riordan, Ted Robinson, Brett Sturgess, Michael Swift, Tom Tierney, Paul Warwick, Brett Wilkinson, Gavin Williams, Darren Yapp.