Sporting applied pressure on Primeira Liga leaders Benfica with a 1-0 victory over Vitoria Guimaraes on Saturday.
With Benfica visiting Sporting Braga on Sunday, their city rivals moved to within four points at the top thanks to Marcos Rojo's strike early in the second half.
Chances were at a premium in the opening half with only two efforts causing concern for either goalkeeper.
Crivellaro had the best chance for the visitors as his long-range effort swerved wide of goal, while Islam Slimani saw a headed effort drop wide on a rare Sporting attack.
When the opening goal did come, Sporting needed a little bit of luck to beat goalkeeper Douglas Jesus.
Four minutes into the second half, Rojo controlled a loose ball on the edge of the penalty area, turned and fired towards goal with the ball deflecting off Moreno on its way into the net.
Sporting could have extended their lead when substitute Fredy Montero had the ball in the net on the hour, but the forward was judged to have been offside in the build-up and his effort was ruled out – although replays showed it should have stood.
Guimaraes pushed for an equaliser but found their finishing lacked accuracy, with Rui Patricio not called upon to make a save.comments