Ireland and Lions flanker Stephen Ferris has been ruled out with a niggling ankle injury, allowing New Zealand recruit Tamaiti Horua to come in on the blindside for his first Magners League start, while stand-in skipper Chris Henry starts at number 8 and Robbie Diack drops to the replacements.
In the backs, Ian Whitten pairs up with fellow Ireland international Darren Cave at centre, deputising for Paddy Wallace who is being rested under the IRFU 2011 World Cup Player Manager Programme.
On the eve of the top of the table clash, Ulster coach Brian McLaughlin commented: "Tomorrow night we have to match the level of performance we produced against the Ospreys and Bath. We have to produce this week in, week out. Not as a one-off, or occasionally, but consistently.
"The squad have trained hard this week, to ensure that we're at our optimum level on Saturday. If we're at our optimum level then I think we'll be okay.
ULSTER (v Leinster): Clinton Schifcofske; Timoci Nagusa, Darren Cave, Ian Whitten, Andrew Trimble; Ian Humphreys, Isaac Boss; Tom Court, Nigel Brady, BJ Botha, Dan Tuohy, Ryan Caldwell, Tamaiti Horua, Willie Faloon, Chris Henry (capt).
Replacements: Andy Kyriacou, Bryan Young, Ed O'Donoghue, Robbie Diack, Paul Marshall, Niall O'Connor, Simon Danielli.