The Team of Choice found themselves a goal down at half time due to an own-goal by Gary Goldstone, but goals from Brice Aka and Collen Zimba in the latter stages of the game saw Gordon Igesund's team claim a crucial three points.
United had the first chance of the game, midfielder John Arwuah heading wide of goal from Tony Tsabedze corner kick in the first minute, but, in what was an evenly matched first 45 minutes, AmaZulu soon created a chance of their own that saw defender Pere Ariweriyai head on target, with the visitors' Tashrique Goldman making a comfortable save.
Midway through the first half Lebohang Kukame got on the end of Lynch Pule's corner kick, but his effort was cleared away by Kampamba Chintu, while Goldman was forced into an excellent save to keep out Thabo Mabaso's shot-cum-cross.
On 27 minutes AmaZulu's Dumisani Ngwenya met Nhlanhla Zwane's cross with a powerful shot, but the ball flew wide of the upright, much to the relief of United's defence.
As the first half wound down, Kukame headed just over the bar for United, but an unfortunate own goal from defender Gary Goldstone in injury time handed Usuthu a 1-0 lead at the break. The ball deflected off the United player after a shot from Ngwenya.
In the early minutes of the second half Kukame twice failed to hit the target for the Team of the Choice, as they went in search of an equaliser, but on 64 minutes they needed 'keeper Goldman to make a fine save from Ariweriyai's header to keep them in the game.
With 20 minutes to play, Maritzburg United drew level. Fullback Peter Petersen picked out Aka with a cross from the right flank, and the Ivorian diverted the ball past Mashudu Mamphitha in the Usuthu goal to make it 1-1.
Three minutes later substitute Zimba completed the visitors' comeback with a low shot inside the penalty area that hit the back of the net; 2-1 to United. Petersen and Aka combined again in the 76th minute, but this time the hosts' goalkeeper was equal to the task.
AmaZulu substitute Bradley Ritson almost made himself the hero in the 88th minute when he met Japhet Zwane's cross, but the ball rebounded off the woodwork and away to safety.