This Saturday's home Guinness Pro-12 league showdown is "crunch time" for Ulster.
That was the view of Iain Henderson, talking to the press at a Kingspan Media Day ahead of the big match.
"We really need to knuckle down on our detail this week and make sure we can execute the game that we know we can play.
"Of course Leinster are a great side with so many internationals but we need to just concentrate on ourselves.
"They have an excellent defence. We need to make sure our defence is at the top of it's game," he said.