Lock Sitaleki Timani will come into the New South Wales side to replace injured number eight Wycliff Palu ahead of the final-round Super Rugby clash with Queensland on Saturday.
Palu was injured in the Waratahs' loss to the Brumbies in Sydney on Saturday night.
Timani will slot into the second row alongside Kane Douglas, with Dean Mumm moving to blindside flanker to cover Dave Dennis, who will take over at number eight.
"Dave has been one of our form players this year and we are very confident in his all round skill set," Waratahs coach Michael Foley said.
"Having him play at number eight is not new to us and it allows us to pick Sita in the second row alongside Kane."
Prop Paddy Ryan will earn his second start of the season after a strong game against the Australian conference-leading Brumbies.
"Paddy's performance against the Brumbies was most pleasing for someone coming back from an extended injury and having played only two club games," Foley said.
"He is a young player who was progressing particularly well before injury and it's excellent to see him pick up where he left off."
Sekope Kepu remains unavailable due to a calf injury, meaning Jeremy Tilse retains his place on the bench.
The clash will be a milestone for winger Drew Mitchell, who will become the 25th Australian player to earn his 100th Super Rugby cap - as long as Brumbies hooker Stephen Moore takes the field earlier on Saturday for his own century.
The Reds' finals hopes are riding on a bonus-point win and a slew of other results, while the Waratahs are looking to close out their 2012 campaign on a high note.
"It's not about us trying to spoil their year or anything like that," Mitchell said.
"I had four years there (with Queensland) and I guess the irony is it's my 100th this weekend and I get to play where it started."
It will be an especially sweet moment for the 28-year-old given the injury-interrupted nature of his season.
"It's taken me 16 or 17 months to get the last four but it was always something I wanted to achieve," he said.
"Their intent will be to go out there and score four tries and it could one of two ways,'' he said of the Reds' gameplan.
"They could at their lethal best, which is a pretty dangerous prospect. They are obviously capable of scoring tries but I think there is a risk there. If they are going out there intent on scoring tries, it might loosen up a little bit.
"The thing for us is we've just got to understand we don't have to change our game entirely - we're doing a lot of good things.
"We've got enough motivation at the moment to go out there and be up for this game, whether it's the Reds or not."
Waratahs: Adam Ashley-Cooper, Lachie Turner, Rob Horne, Berrick Barnes, Drew Mitchell, Bernard Foley, Grayson Hart, Dave Dennis, Chris Alcock, Dean Mumm, Kane Douglas, Sitaleki Timani, Paddy Ryan, Tatafu Polota-Nau, Benn Robinson.
Replacements: John Ulugia, Jeremy Tilse, Lopeti Timani, Jono Jenkins, Brendan McKibbin, Tom Carter, Tom Kingston.
Tags: super-rugby, rugby-union, sport, sydney-2000, nsw, australia First posted July 11, 2012 15:32:32