The result sets Saints up nicely for tomorrow night’s top-of-the-table clash at Park Hall against second-placed Bala Town, who had to settle for a point from a 1-1 draw at home to Cefn Druids.
McManus struck just before the hour at the Deeside Stadium, keeping his cool to confidently find the net from the penalty spot.
The spot-kick was awarded following a challenge from former TNS player Jamie Mullan on Jordan Williams.
“It’s a tough place to come, it’s always a battle,” said TNS captain Chris Marriott afterwards. “You’ve got to win your battles first before you can play your football. I thought we did that at the right times. We’ve competed with them physically and then I thought there were spells in the game where we played some good football, so, yes, it was a good feeling to have the three points today.”
There were few clear goalscoring chances in the first half, although as it progressed a deflected effort from TNS midfielder Jon Routledge was deflected narrowly wide.
Danny Redmond then curled an effort just off target before, on the stroke of half time, McManus saw a powerful shot tipped over the crossbar by home goalkeeper Oliver Byrne.
Ben Clark had a shot blocked just after the restart, with Ryan Brobbel next to go close for Saints with an effort past the far post.
After McManus gave Saints the lead, Nomads, the defending champions, pushed for an equaliser, with Danny Holmes drilling a shot wide and Aeron Edwards heading over the crossbar.
Both teams were reduced to 10 men three minutes from time when TNS defender Keston Davies and Nomads’ George Horan were sent off following a confrontation.
Nomads thought they had secured a late point when Declan Poole found the net, but the effort was disallowed as Saints added three more points to their tally.
TNS: Harrison, D, Davies, K. Davies, Astles, Marriott, Clark (Cieslewicz), Routledge, Redmond, Brobbel (Baker), McManus, J. Williams (Robles). Subs not used: Ebbe, Leblanc-Akpo, Holland, Parry.
n Market Drayton Town crashed out of the FA Trophy at the second qualifying stage after losing 7-0 at home to Leek Town.