Benni McCarthy named Siphelele Mthembu as the lone man up front ahead of Lehlohonolo Majoro, while goalkeeper Sanele Tshabalala continued in goal for Swallows.
Usuthu, who entered matters on the back of two straight losses to Baroka FC and the might of Orlando Pirates, looked to cement second spot with a return to winning ways.
This appeared to be the case in the earlier exchanges through quick fire shots from Siyethemba Sithebe and Xola Mlambo, but the Dube Birds rear-guard remained steadfast at the back.
AmaZulu put on a substitution at the start of the second half, with Majoro called off the bench in favour of the veteran Mthembu.
It proved the perfect stimulus as within seconds, Usuthu were awarded a penalty following a handball in the area, and Tapelo Xoki stepped forward to fire in the opener.
Swallows came close to pull themselves all square midway through the second half with a solid strike from Musa Nyatama, but goalkeeper Veli Mothwa was up to the task.
The Dube Birds didn't stop to launch their pursuit for the equaliser in the closing minutes, but Usuthu stayed strong to confirm the win and second spot in the process.
AmaZulu: Mothwa, Sikhakhane, Mabiliso, Xoki, Gumede, Mlambo, Kewuti, Sithebe, Chawapihwa, Qalinge, Mthembu.
Subs: Boshoff, Mzava, Mgwazela, Masilela, Maduna, Ncube, Mulenga, De Jong, Majoro.
Swallows: Tshabalala, Mere, Sait, Ngcobo, Matlaba, Thibedi, Nyatama, Mokoena, Sekgota, Mbokoma, Gamildien.
Subs: Ngobeni, Sibiya, Khupe, Ritchie, Basadien, Mzwakali, Malinga, Senwamadi, Mahlatsi.