The Brazilians confirmed the signing on their official website.
READ: Sundowns snap up Ghanaian goalkeeper – reports
The 30-year-old joins Sundowns on a free transfer after leaving Spanish second-tier side Cordoba.
“Razak, who has played for the Ghana national team, and played in the epic Africa Cup of Nations final against Ivory Coast which Ghana lost 9-8, has joined the Brazilians on a five-year contract,” read a statement on the club’s website.
Brimah will be competing with Denis Onyango and Kennedy Mweene for the number one spot at Sundowns.
READ: Why Sundowns could be forced to sell Billiat
Meanwhile, Sundowns are said to be considering retaining Thela Ngobeni. The 28-year-old shot-stopper spent last season on loan at Free State Stars last season.
If retained, Ngobeni will be the fourth-choice goalkeeper at Sundowns.
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