Waratahs fly-half Bernard Foley has admitted that it was a painful process dissecting what went wrong after the side's loss to the Rebels.
A poor first half left the 2014 champions trailing 3-21, and despite a second-half comeback they were unable to flip the result in their favour.
The Waratahs' third loss of the year leaves them trailing the Brumbies and Rebels by six points in the Australia Conference heading into their bye week.
Foley pointed to "a lack of maturity" when it came to the Waratahs sticking to their gameplan as a factor in Sunday's poor performance.
“It wasn’t a pretty review. Very honest,” he told AAP.
“We probably went outside of our systems and showed a lack of maturity in that regard. To be honest, from a backline point of view, we weren’t up to scratch.
“Having a bye week, we can really have a look at ourselves individually but also as a unit and collectively find where we can get better and where we’re going to have to be better against the Brumbies.
“It’s about just having trust in what we do, getting repetition in that and guys not going outside of that… rather than trying to make a quick fix.”