Cullen says Ulster clash the most important derby of the festive season
Leo Cullen has admitted that this evening's meeting with Ulster at the RDS is the most important of the three his Leinster team have faced over the past 11 days.
Although wins over Munster and Connacht were satisfying, those two opponents were rivals in name only given they are in Conference A in the Guinness PRO14, meaning they are not in direct competition with the eastern province.
Ulster, however, are just six points behind second-placed Leinster in Conference B and so the result will have a far more serious bearing on the eventual outcome of both sides' seasons.
Cullen has again made sweeping changes for the Ballsbridge clash, while Les Kiss is able to call on fit-again Rory Best and Iain Henderson who was rested for the dramatic win over Munster on New Year's Day.
And the Leinster coach says this is the biggest of the three games to date.
"Definitely. You think in our conference, we're competing against those teams," he said.
"We're playing against the other teams (in Conference A), but we're not necessarily competing against them which is a different dynamic to what we're used to.
"Scarlets are on top, so we're very conscious of what they're doing. Ulster as well, behind us, Edinburgh behind them, so yeah, Ulster and Scarlets are the one we're most focused on.
"I'm not looking at the other conference, I don't know what's going on over there."
Jack McGrath captains the Leinster side as Cullen picks his strongest available tight-five, while youngster Josh Murphy becomes the 37th player to feature for the province during their three games since beating Exeter Chiefs at home.
As well as Best and Henderson, Les Kiss can call on Jacob Stockdale in the back-three, while Ireland U-20 scrum-half Johnny Stewart is handed his first Ulster start.
Munster, meanwhile, are looking for their first inter-provincial win in five attempts against a weakened Connacht side at Thomond Park.
Johann van Graan hands CJ Stander the captaincy of his team for the derby, with Peter O'Mahony on the bench.
Otherwise, the Reds coach fields his strongest available team with Chris Farrell back in the centre as Conor Murray returns to partner Ian Keatley at half-back.
Connacht coach Kieran Keane has rotated his squad and makes the trip without Ireland trio Ultan Dillane, Kieran Marmion and Bundee Aki after their efforts against Leinster on Monday.