Mansfield's Sam Clucas ended Newport's 100% home record as he rescued a draw as both sides finished with 10 men.
Newport led through Chris Zebroski's first-half headed goal, converting Adam Chapman's wickedly in-swinging corner.
But Mansfield got back on level terms after the break as Clucas scored from a similarly well-worked corner.
Newport's Lee Minshull was sent off for leading with his elbow on Martin Riley, but Mansfield's Matt Rhead soon followed for a second yellow card.
VIEW FROM THE DRESSING ROOM
Newport County manager Justin Edinburgh told BBC Radio Wales:
"I'm disappointed, not with the effort and commitment as I never doubt that from my players, but I didn't think we were brave enough or good enough in possession of the ball and that's probably the worst we've played for a long time
"Everyone got caught up in the physical side of the game and... we were 100 miles an hour and trying to get in with one pass, but I can't criticise them for the way they competed.
"It was a heated game, there was one or two incidents that were let go where I thought that if they were dealt with early on then the game wouldn't have got a little bit out of control."
Mansfield Town manager Paul Cox told BBC Radio Nottingham:
"I thought we were unlucky not to come away with all three points from the chances we had in the first half alone. If we had taken two or three of the chances we created in the first half we would have been out of sight.
"But it's a tough place to come. We would have probably taken a point before the game but I just feel we were probably worth a little bit more.
"I think we are getting better at a lot of things. The players are building a belief and spirit and we were resolute throughout the game. Alan Marriott has only had one save to make apart from the goal.
"But we found a goalkeeper in inspired form. If we just had a bit of luck up top we could have got all three points."