Downs are understood to be willing to break the bank and offer up to R23 million to bring Brockie to Chloorkop.
The Kiwi scored 10 goals in 17 games for United.
Meanwhile, Sundowns are said to be willing to bring former Kaizer Chiefs defender Tefu Mashamaite.
According to a source close to the Brazilians, Mashamaite is seen as a perfect replacement for Alje Schut, who returned home to the Netherlands.
Earlier, there was talk that Mashamaite had already agreed a deal with Sundowns, however, his agent Jazzman Mahlakgane later told Phakaaathi that was not the case.
Downs fans, have your say. Should Sundowns pay R23 million for Brockie?
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