Having snubbed the national team last week so that he could concentrate on his club duties, Santo was again in the thick of the action as Union beat Mtibwa Sugar 3-1.
Juma jabu, Daniel Lyanga and Lameck Dyaton were on target for Union while Mtibwa's goal was scored by Salum Sued.
The match wa played at Union's Mkwakwani Stadium home in Tanga.
They remain fourth in the league standings with 13 points from eight matches played this season. Leaders Simba have a five point lead over Union.
Union's next match will be against African Lyon on Wednesday 24 October 2012.