The drubbing was their worst ever defeat in league football and matched their 7-1 FA Cup beating to Belper Town in 1960.
“We can’t defend - just the basic principle of defending,” he said. “All through the game we couldn’t defend - every time they had an attack it was causing us problems.
“The most disappointing thing is that they’ve not really had to work for any of the goals and not being able to defend in any way, shape or form.
“We knew we could get at them, we knew if we put pressure on them there were goals, the door opened slightly when we got back to 1-3, then literally the last act of the first half the lad has a free header in the six-yard box - we were poor.”
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Heath also felt the Reds were on the wrong end of refereeing decisions.
“The penalty we conceded for the first, l’m not sure about,” he added.
“We know we don’t get anything off referees, because we’re Alfreton. We’re nearly halfway through the season and we don’t get decisions and we have to take that on the chin.
“Two decisions two goals - the free-kick was a soft one and [referring to a lunging tackle by Chandler on Riley that was only shown yellow] the boy stays on the pitch and l think if he’d been in a red shirt it would have gone the other way - but we can’t shy away today - when the back four can’t defend you’ve got problems.”