Alan Curbishley believes Felix Magath must address Fulham's dismal defensive record if they have any chance of survival.
The rock-bottom Cottagers have conceded 59 goals in just 27 games - 11 more than their nearest Premier League rivals.
Magath was denied a dream start as boss after Fulham were held to a 1-1 draw at West Brom on Saturday.
And Curbishley, who was axed from his role as technical director following Rene Meulensteen's dismissal, insists they need to shore up their leaky backline if they are to escape relegation.
"The glaring thing is the amount of goals Fulham have been conceding," he told Sky Sports News .
"If you look at the clubs who have dragged themselves out of the relegation zone this season - Crystal Palace and West Ham - that's been done on clean sheets.
"And they will always give you a chance of getting something from games.
"Against West Brom they got their noses in front but just couldn't get across the line.
"They made a decent start and it's always important to get ahead. They've gone one behind on about 19 occasions this season and history tells you in the Premier League that if you fall behind you don't get back that often."
Curbishley admits he was disappointed to be shown the door after less than two months at Craven Cottage.
However, he says the news didn't come as a surprise.
"There was a change of manager who decided he wanted to bring his own staff in," Curbs added.
"That's always a consequence of managerial changes. I understood it, I respected it but I was a little bit disappointed because - when I went into Fulham - the role I had was something the club needed.
"There are some inexperienced managers in the Premier League such as Tim Sherwood at Tottenham and Garry Monk at Swansea, so there is a role for ex-managers to be mentors."
"Rene had never been a manager before and I was there to advise and offer my opinion on things, as was Ray.
"There are some inexperienced managers in the Premier League such as Tim Sherwood at Tottenham and Garry Monk at Swansea, so there is a role for ex-managers to be mentors.
"But unfortunately it only lasted seven weeks.The owner decided after the Liverpool game he was going to make a change.
"Rene will be disappointed, as it was his first stab at management, because the two games previously against Manchester United - where we drew - and against Liverpool, when we led twice, we felt the tide was turning a little bit."