Cobblers boss Keith Curle believes individuals are at fault rather than the system after defending his decision to go with zonal marking from set-pieces.
For the second week in a row Town conceded from a corner during Saturday's wind-swept 1-1 draw against Port Vale.
After James Clarke headed Walsall in front on the opening day of the season, David Amoo did likewise at Vale Park seven days later when afforded the freedom of the penalty box to nod home David Worrall's corner.
Explaining what went wrong in that particular situation, Curle said: "Without picking out anyone, there was a person designated to head that ball in the middle of the goal.
"But because of what happened from previous corners he thought he'd go and help out someone else at the back post.
"Lo and behold the header goes in so it's his responsibility, but we're learning about each other and the players are getting that understanding of what I want."
Ryan Watson scored a header of his own to drag Cobblers level and ultimately earn a point on Saturday, but Amoo's goal was not the only time Curle's side looked vulnerable from set-pieces.
The Town manager defended the system afterwards though, adding: "There's a level of frustration because we worked on it and we got the understanding of what's required and the positional play, but players do change their mentality on the pitch.
"They maintain their starting point and then they see something happen and try and do what they think is the right thing but ultimately it's the wrong thing.
"It's just down to spending more time on the coaching ground and identifying things on the videos because it should have been stopped if personnel are in the right place to deal with it.
"It's a learning curve for some of the new players in the way we zonal mark and you've got to say previously it has given us rewards.
"Now we're being tested and it's about the belief and the honesty to take onboard new demands. I'm not scared of it if I think it works."