Sporting Lisbon have been held to a goalless draw by Boavista, despite enjoying over 70% of the possession.
Adrien Silva was first to threaten but his shot in the fourth minute missed the target.
Fredy Montero and Islam Slimani both had shots blocked during a quiet first half.
Despite Sporting's dominance in possession, the Boavista defence was able to withstand the pressure and limit the chances.
Gelson Martins shot from 10 yards went wide of the target before Teofilo Gutierrez also missed the target on the hour mark.
Luisinho and Michael Uchebo had chances to give Boavista the lead, but they also were unable to hit the target on a frustrating evening for the neutrals.
Slimani forced a save from Michael Mika in the 76th minute as the game finished goalless.
Renato Santos had a chance in stoppage time to give Boavista an unlikely victory but Rui Patricio kept the shot out.
