Danny Welbeck's late finish helped Arsenal see off a defiant Sporting CP side to go top of their Europa League group and extend their winning run to 11 games.
The hosts had joy on the counter against Unai Emery's side, while Henrikh Mkhitaryan tested Ruben Ribeiro with a powerful free-kick after Mohamed Elneny was felled on the edge of the box.
Despite early warning signs Arsenal's insistence to play out from the back provided the hosts with a number of chances; Nani won possession from Holding's wayward pass but fired over from distance.
Pierre-Emerick Aubameyang went close twice in quick succession after the break, denied both times by the impressive Ribeiro, first saving well from an angled drive before standing tall to swat away Aubameyang's dinked effort.