Folarin Balogun was the first to threaten, and nearly broke a seven-game drought in front of goal, after his left-footed shot was deflected narrowly wide of the post in the eighth minute.
Adingra then bent a brilliant effort just past the post from the edge of the box before Wout Faes was denied from point-blank range by an incredible save as they forced the initiative.
That save was rendered meaningless by a simple error, though, as Abakar Sylla allowed Maghnes Akliouche through on goal in the 25th minute, and his strike was palmed into the path of Adingra, who made no mistake in opening his Monaco account.
The Ivorian was celebrating again just three minutes later, as he secured a brace after finishing well on the end of Aleksandr Golovin’s perfectly weighted ball.
And Nantes’ goal difference took a further hit as they conceded another two minutes after – it was a tale of same provider, different scorer, as Golovin assisted midfielder Denis Zakaria for his first of the season and all but secured the hosts’ second victory in three league outings.
After a calm spell, however, Nantes managed to pull one goal back in added time, when defender Fabien Centonze netted his third of the season with a brilliant finish after a smart pullback.
Though that looked to be a mere consolation, Nantes took some confidence from that and dominated the possession after half time.
Whilst there was little quality on show, Golovin’s dismissal via a second yellow card gave them renewed hope as Monaco looked to hold on for a rare victory.
There would be no miracle fightback, though, and with this victory, Sébastien Pocognoli’s side have provisionally moved up to seventh place, while also going within two points of Lille in the European qualification zone.
As for Nantes, this was a fifth straight defeat, and potentially a very costly one, as unfavourable results this weekend could see them fall 11 points adrift of definite safety.
Flashscore Man of the Match: Simon Adingra (AS Monaco)