Newport County had beaten Grimsby Town 1-0 at Rodney Parade earlier in the season
Jordan Cook scored twice as Grimsby Town moved above Newport County in League Two with a deserved 3-0 victory at Blundell Parl.
Cook opened the scoring, his effort from the edge of the area beating Nick Townsend in the Newport goal.
Townsend saved a Wes Thomas penalty after Keanu Marsh-Brown fouled Cook.
But Cook's deflected shot made it 2-0 before Martyn Woolford's shot ricocheted off Mickey Demetriou to beat his own goalkeeper Townsend.
Grimsby move up to 12th in League Two while County are 14th.
Newport County manager Michael Flynn said: "Shocking. Terrible defending - we didn't track runners, lazy defending. It was nothing to do with the conditions.
"The first 15 minutes we were excellent and then it was terrible. It was weak, poor and wasn't good enough.
"We made a few changes and I thought what we put out was good enough to win a football match. Obviously it wasn't and it told me a few things about a few people."
