The visitors had a great chance to take the lead in the opening 30 seconds of the game when Gerso latched on to a cross in the box, but he put his effort wide of the post.
Lisbon hit back with a good opening as Islam Slimani rose highest in the box to head at goal, but his attempt went just over the bar.
Estoril wasted another good opportunity when Bruno Cesar found space inside the penalty area, only to put his strike wide of the post.
Cesar got in behind the Sporting defence down the right flank, and without support tried a strike from a tight angle, but Rui Patricio made the save to deny the forward.
In the second half, Sporting were handed the chance to take the lead when Teofilo Gutierrez was brought down in the box and a penalty was awarded. Gutierrez took the spot kick and fired his strike into the bottom corner.
Jefferson should have doubled his side's advantage as he latched on to a cross at the back post, but he somehow missed the target from close range with the goal gaping.
Fredy Montero almost notched the home side's second goal when he unleashed a powerful strike from distance, but his strike was well saved by Pawel Kieszek.
Cesar came within inches from equalising for the visitors as he drilled a left-footed strike at goal from the edge of the box, only to see his effort clip the bar and sail over, allowing the home side to hold out for the win.