Usuthu have joined the race for the services of Ntuli, who is also wanted by Platinum Stars following his stints on loan at Dikwena over the past two years.
The Brazilians previously farmed Ntuli out to AmaZulu for six months in 2015.
"AmaZulu has identified Ntuli as one of their main targets to reinforce for the new season," says a source close to the Durban-based outfit.
"The offer has been made and they are waiting for Sundowns to respond."
The Premiership returnees on Tuesday confirmed the capture of defender Ayabulela Konqobe from Richards Bay FC.
AmaZulu recently bought the topflight status of Thanda Royal Zulu, prompting the formation of NFD outfit Richards Bay.
Joey Antipas's side have also recruited Sadat Ouro-Akoriko, Sduduzo Dlamini, Jabulani Ncobeni, Siyabonga Mbatha and Siyethemba Mnguni in the off-season.