Leinster have installed an extra 630 seats at the RDS for Saturday week’s Guinness PRO14 semi-final against Munster.
They will bring the capacity for the game to just under 19,000.
Head of Commercial & Marketing at Leinster Rugby, Kevin Quinn, said: "As expected the demand for this game from our Season Ticket Holders and wider supporter base has been huge and we were keen to meet that demand as best we could.
"We have seen how special a place the RDS can be for games like these and in particular for interprovincial games and we were keen that we accommodated as many supporters as possible and in doing so, help make the RDS a cauldron of noise for Leo and the team."
The Blues are set to jet off to Bilbao this evening following training as they embark on a massive 14 days in the province's history.
Leo Cullen's men will face Racing 92 in the Champions Cup final on Saturday before facing Munster the following week and then a possible PRO14 final on May 26 at the Aviva Stadium if they can beat their provincial rivals.