Chris Clements' early goal sealed a 1-0 win for Mansfield to leave Newport searching for their first point of the season.
The struggling visitors gifted the Stags the lead after less than 90 seconds when Clements scrambled home Lee Beevers' cross.
Simon Heslop then brought the best out of Newport goalkeeper Lenny Pidgeley after good work by Alex Fisher carved County open.
But the Exiles fought back strongly and nearly equalised through Chris Zebroski's snapshot which was beaten away by Sascha Studer.
Andy Sandell's curling free-kick was palmed away by a diving Studer as the visitors dominated before the break.
Matt Rhead blazed Beevers' cross over the bar after the interval as Mansfield looked to seal victory.
At the other end, Kevin Freely saw his shot blocked before Robbie Willmott fired wide as the visitors continued to push.
Clements then blew a one-on-one with 20 minutes to go as Pidgeley saved well.
Former Stag Aaron O'Connor hit a fierce effort inches wide in the closing stages, an indication that it was not going to be Newport's night.