The 42-member delegation landed in the Rwanda capital in the early hours of Saturday to fine-tune preparations for the crucial match.
The Brazilians will train at the Mumena Stadium to gauge their readiness for the encounter.
In the Sundowns squad are familiar faces including captain Hlompho Kekana, Denis Onyango, Percy Tau, Khama Billiat and Jeremy Brockie.
Meanwhile, Rayon who edged Lydia Ludic of Burundi at the preliminary round with a 2-1 aggregate will be without central defender Thierry Manzi, who is suspended for the tie. Manzi was cautioned in both legs of the previous round clash against Lydia Ludic last month.
The return leg will take place on Sunday, 18 March 2018 in Pretoria with the winner qualifying for the lucrative group stage.
Tuesday, 6 March 2018
Al Ahly (Egypt) vs Mounana (Gabon)
Horoya (Guinea) vs Generation Foot (Senegal)
Young Africans (Tanzania) vs Township Rollers (Botswana)
Etoile du Sahel (Tunisia) vs Plateau United (Nigeria)
Wednesday, 7 March 2018
Saint George (Ethiopia) vs KCCA (Uganda)
Zanaco (Zambia) vs Mbabane Swallows (Swaziland)
Wydad Athletic Club (Morocco) vs Williamsville AC (Cote d’Ivoire)
Aduana (Ghana) vs ES Setif (Algeria)
MFM (Nigeria) vs MC Alger (Algeria)
Gor Mahia (Kenya) vs Esperance (Tunisia)
AS Togo (Togo) vs El Hilal (Sudan)
Zesco (Zambia) vs ASEC Mimosas (Cote d’Ivoire)
TP Mazembe (DR Congo) vs UD Songo (Mozambique)
Difaa Hassan (Morocco) vs AS Vita (DR Congo)
Primeiro de Agosto (Angola) vs Bidvest (South Africa)
Rayon Sports (Rwanda) vs Mamelodi Sundowns (South Africa)