Brian Laws acknowledges Scunthorpe must stop conceding goals if they are to lift themselves out of the relegation zone.
The Iron have leaked 43 goals in their 23 league outings this term to leave them with a goal difference of -19 meaning just basement dwellers Hartlepool, the only team below Laws' outfit, have a worse differential.
Scunthorpe have not kept a clean-sheet since September and Laws admits they must rectify their failings at the back.
"It is like losing an extra point given how tight the league is," Laws told the club's official website.
"We are giving away some silly goals and they could be costly in the end because we are conceding the amount of goals that, at some stage, will affect us.
"We have to stop that - it isn't going to be easy, we know that."