Felix Obada and Kurt Lentjies did the damage for Maritzburg.
The loss is the fourth in five games for Abafana Bes’thende, while the Team of Choice have kept up their unbeaten start to the season.
Maritzburg opened the scoring as early as the ninth minute when Felix Obada unleashed a powerful shot to the top corner after receiving a long pass from Peter Petersen.
The visitors played positively in search of an equaliser but they were kept out by some resolute defending from Ian Palmer’s team, who successfully maintained their lead until the half-time break.
After the break it was Arrows who started as the better side with Thanduyise Khuboni and Katlego Mashego shooting over the bar in the 48th and 52nd minute respectively.
United had a penalty shout turned down at the other end shortly afterwards when Diyo Sibisi went down as he tried to round the keeper, but the referee booked the striker for simulation instead.
With United protecting their lead, Arrows were mostly restricted to taking shots on the edge of the box and Mashego saw his shot tipped over the bar by Shu-Aib Walters in the 56th minute.
Obada had the perfect to chance to grab his second goal of the match in the 57th minute when he was put through by a great pass from Sibisi, but Virgil Vries did well to parry the ball away, effectively keeping Arrows in the game.
United effectively killed off the match in the 78th minute when Obada was brought down by Musa Bilankulu about 20 yards from goal.
Lentjies stepped up to take the free kick and beat the goalkeeper to put the home side 2-0 up.