Both sides started like a house on fire as both battled for a spot in the final, however, it was the hosts who found the net in the ninth minute when Bongani Zungu scored, but it was disallowed as it was a hand ball.
Pitso Mosimane’s men continued to keep United under pressure and their efforts were rewarded when Leonardo Castro netted his first goal for Sundowns in the tenth minute after finishing a cross from Themba Zwane, 1-0.
Gordon Igesund’s charges equalised three minutes later when David Mathebula netted from a perfect set piece, 1-1.
Mosimane’s men took the lead when Thabo Nthethe scored a great header in the 61st minute when he received a great delivery form a short corner played by Dolly, 2-1.
In the 80th minute Zungu made it three when he finished in the box after a brilliant run down the left wing.
In the dying minutes, Sundowns enjoyed possession and ensured they killed the game with their possession football.
The win means the Brazilians will meet Kaizer Chiefs in the final of the TKO Cup after beating Orlando Pirates in the Soweto Derby on Saturday afternoon.