The striker gave the home side the lead in the 21st minute when he collected Seth Sinovic's pass on the edge of the area and fired a low shot past Joe Bendik.
Sporting doubled their lead after the break when Saad got his second of the game. Bendik parried Graham Zusi's shot into his path and he made no mistake in slotting the ball into the net.
Toronto were then reduced to 10 men as defender Reggie Lambe was given his marching orders for a reckless challenge on Saad.
Kansas got their third of the game when Claudio Bieler found the net following a lovely team move as Benny Felihaber crossed for the Argentine, who was left with a simple finish.
Aurelien Collin nearly added a fourth for his side when he headed a loose ball into the net, but he was ruled offside.