The fast-paced match was goalless at half-time, although both sides had some good chances to score.
Maritzburg's Tashrique Goldman and Thomas Ritcher of Aces were the stars on the night, both making some brave saves to keep their teams in contention.
Second-half substitute Davids pounced on a ball from Byron Hendricks in the 78th minute, to give Maritzburg their third win of the season.
Aces ultimately had only themselves to blame, as they allowed the home side to dictate terms in the second half after playing so well in the first stanza.
The game takes Maritzburg to 11th place on the log, while Aces sit in 14th with 12 points.