Through the opening six rounds it was the unforced errors that were hurting the side before second-half lapses in consecutive weeks allowed both the Cowboys and Titans to conjure come from behind victories.
Those late fades were partly attributed to exhaustion from the extra defensive work the Warriors were forced to do on the back of the unforced errors that have plagued the team.
McFadden believes eradicating those basic mistakes will have a positive roll-on effect into other aspects of their performance.
"A bit of that in the second-half is about what we are doing to ourselves in terms of energy and the errors we make," he said.
"We've obviously got to settle on some combinations there but we've got to address that more as a team.
"They're fundamental errors that are confined to a small group of individuals and they've got to take responsibility for that and if we can eliminate those out of our game it's a different story."
Captain Simon Mannering agreed a heavy defensive workload over the first two months of the NRL had taken its toll and impacted on the side's ability to hang tough when defending their line.
"It's probably come off the back of doing a lot more defending than what we should do," Mannering said.
"Obviously that's on the back of errors and we're not using the ball as well as what we could have and turning over a lot of possession.
"It's a flow-on effect from that and if we can get that right, where we're not forcing ourselves to do more work when we don't have to, hopefully our defence gets better and we can put ourselves in a position to get the result."
Last weekend's representative round was positive from the Warriors' perspective, with players involved in both the Anzac test and Pacific Island clash delivering some strong performances.
McFadden saw enough in the individual efforts of both Samoa's Dominique Peyroux and Tonga's Konrad Hurrell to promote them back into the NRL side this week.
"Most definitely, with the try he (Peyroux) scored and the energy he brings. He played a very similar role that he's been playing with us in the middle of the field to go on and bring energy," he said.
"I'm expecting him (Hurrell) to reach a standard. He's obviously got an awesome game in certain areas but defensively he needs to really measure up."
Meanwhile, fullback Sam Tomkins' comeback from a knee injury has been delayed with the England international now eyeing a return in the round 12 home game against Newcastle.
"We were hopeful we'd get him back within the more aggressive timeline of six weeks but he's probably going to be another couple of weeks on the sidelines," McFadden said.
"He's unlikely for the Parramatta game next week so hopefully we'll get him back after the bye."
