Wallaby number eight Wycliff Palu returns to the Waratahs starting XV for Saturday's clash with the Hurricanes in Sydney.
As one of a handful of changes made by coach Michael Cheika, Palu is promoted from the bench in a back-row reshuffle following last weekend's loss to the Blues in Auckland.
Skipper Dave Dennis shifts to blindside flanker to accomodate Palu's retrun, while Jacques Potgieter moves into the second row.
Will Skelton drops to the bench for a match the Waratahs must win to retain a place in the top six ahead of their bye next week.
In the front row, with Paddy Ryan to start at tighthead instead of Sekope Kepu.
In the backs, Matt Carraro replaces Cam Crawford on the wing, while Alofa Alofa, who is hoping to return from injury on the bench.
"First of all, it's great motivation having Cliff back," said vice-captain Michael Hooper.
"It will be nice to have the big man back. His physicality and the opposition knowing he's in the team is a good (thing) to have."
After a slow start to the season, the fourth-placed Hurricanes have surged to the top of the New Zealand conference after a string of wins.
"They're certainly playing some really good football. They've changed their style of attack and how they go about things and it seems to be working for them," said Waratahs centre Adam Ashley-Cooper.
"So they're certainly competing up there with the Chiefs and they're obviously leading the New Zealand conference ladder for a reason. They're a good team.
"For us, it's a really big game. We're at home, we need to win. Obviously it wasn't the result we wanted last week and I feel this game could define our season."
Waratahs:15 Israel Folau, 14 Matt Carraro, 13 Adam Ashley-Cooper, 12 Kurtley Beale, 11 Rob Horne, 10 Bernard Foley, 9 Nick Phipps, 8 Wycliff Palu, 7 Michael Hooper, 6 Dave Dennis (c), 5 Jacques Potgieter, 4 Kane Douglas, 3 Paddy Ryan, 2 Tatafu Polota-Nau, 1 Benn Robinson.
Replacements (two to be omitted): 16 Tola Latu, 17 Jeremy Tilse, 18 Sekope Kepu, 19 Will Skelton, 20 Stephen Hoiles, 21 Pat McCutcheon, 22 Brendon McKibbin, 23 Jono Lance, 24 Alofa Alofa, 25 Cam Crawford.
Date: Saturday, May 3
Venue: Sydney Football Stadium
Kick-off: 19.40 local (09.40 GMT)
Referee: Steve Walsh (Australia)