All three goals were scored in the second half, with the hosts going 2-0 up before a 10-man United pulled one back late on.
Stars were close to taking the lead in the opening seconds of the game when Goodman Dlamini fired a in a left footed effort from just outside the box, which deflected off the post.
In what was a tightly-contested opening half in the Free State, Maritzburg midfielder Mxolisi Khunene sent a 17th minute shot over the bar, while at the other end, Dlamini also sent a drive over goal.
The Team of Choice were almost ahead 15 minutes after the interval as Siphesihle Ndlovu's 20-yard shot narrowly missed.
But instead the KZN capital city club were to find themselves 1-0 down in the 65th minute when Harris Tchilimbou converted from the penalty spot.
New Team of Choice signing Keletso Makgalwa was then unlucky not to equalise seven minutes later when he smacked a shot into the post from just outside the box.
It just wasn't to be for United though as Fortune Makaringe was sent off in the 85th minute after picking up a second yellow card before Dlamini curled a shot in at the near post three minutes later to extend Ea Lla Koto's advantage to two.
Makgalwa was to pull back for the visitors with a close range effort in the 90th minute, but Maritzburg were unable to salvage anything from their midweek excursion to Bethlehem.
Next up is our MTN8 showdown with Cape Town City at the Harry Gwala Stadium on Sunday.
Maritzburg Starting XI: Ofori, Sanoka, Xulu, Shandu, Thlone, De Reuck, Ndlovu, Atouba, Makaringe, Mokate, Kunene.
Subs: Mpandle, Mekoa, Matima, Farmer, Buchanan, Masegela, Makgalwa.
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