Goodman Dlamini cancelled out Luvhengo Mungomeni’s first-half strike, but Lerato Chabangu struck soon after to secure maximum points for the Birds.
After a quiet start, it was the hosts who opened the scoring just before the half-hour mark. Chabangu delivered a free-kick into the box and it was Mungomeni who rose highest to glance the ball into the back of the net.
Usuthu found the equaliser just before the hour-mark when Nhlanhla Shabalala’s cross fell for G. Dlamini, who beat Greg Etafia with a left-footed finish.
However, Swallows were back in front just four minutes later when Siyabonga Nomvete set the ball up for Chabangu to score his second of the season.
Craig Rosslee’s side tried to claw their way back into the game again, but the Swallows defence kept them at bay with the only chance coming from Van Heerden’s free-kick, which went over the crossbar.
The result leaves Swallows at the top of the standings with six points from two matches, while AmaZulu are placed 13th with one point from their two games.