Right-back Cameron Norman got the ball rolling with a hammer of a free-kick that fizzed into the bottom corner to put County ahead in the 14th minute.

It was 2-0 four minutes later when left-back Tom Davies controlled a loose ball in the box and managed to hook a shot past Zach Hemming in the Chesterfield goal.

Harrison Biggins added a third after half an hour when he tried his luck from distance and caught out Hemming, despite his shot lacking power.

And Yahaya Bamba capped a remarkable first half for the hosts as he took advantage of some static defending to curl a delightful finish beyond Hemming in the second minute of stoppage time.

Chesterfield boss Paul Cook was sent off during the interval and his side appeared to be denied two penalties for apparent handballs.

Liam Mandeville’s fine finish just before the hour was scant consolation.
“It’s definitely the best result (of the season), goals-wise, and the first-half performance was very good,” said Mullins, whose side climb to 10th before Saturday’s games.

“It’s the best 45 minutes we’ve put together this season – the lads blew them away.

“They’re a really good side, they’re tipped to be in and around the play-offs.

“It’s a weird scoreline when you’re 4-0 up at half-time.

“To go back out again and replicate that is tough because you don’t want to let them back in and we knew it would be a difficult second half.

“The goal we conceded is disappointing, but nothing really takes away from our first-half performance – that was top class.”

Chesterfield assistant manager Danny Webb took charge after Cook’s red card and he was in no mood to make excuses after the match.

“The game was done at half-time,” said Webb. “The way they started, the whole ground felt optimism in the Newport camp and a little bit of nerves in the Chesterfield camp. There were a lot of bad decisions – you could say we should have had a penalty – but there are certainly no excuses.”

The big turning point came in the 23rd minute when Exiles midfielder Matt Smith appeared to handle Mandeville’s shot on the line.

“It was a handball and probably a sending off,” said Webb. “But we lost 4-1 so no excuses.

“You have to give a lot of respect to Newport – they had a game plan, they started on the front foot, they were aggressive and physical and we’ve struggled in these sort of games before. We struggled again tonight.”