It looked like Arsenal was set to ensure another frustrating outing, but Havertz came off the bench to net another late goal for the Gunners, giving them a lead to protect next week at the Emirates Stadium.

A lightning-quick start to the match, in which both sides hit the crossbar in the first 15 minutes, did not set the tone, with Arsenal also having a Martin Zubimendi goal disallowed in the second half.

Sporting raced out of the blocks, with Araujo holding off his defender as he raced in behind, and he had David Raya worried, only to sweep his shot against the crossbar.

Arsenal settled into the game shortly after, and Noni Madueke almost caught out Rui Silva with an in-swinging corner that bounced off the bar before Martin Odegaard fizzed a first-time effort narrowly wide.

Despite Arsenal's dominance in possession, Sporting continued to provide a threat on the break, but Trincao got his angles all wrong after being played in by Araujo.

Zubimendi thought he had given Arsenal the lead in the 63rd minute, but his celebrations were cut short. He drilled a low shot into the bottom-right corner from range, but Viktor Gyokeres was offside in the build-up.

Raya then kept Arsenal in the tie, reacting brilliantly to keep out Geny Catamo's improvised finish in the 83rd minute. He kept the Mozambique international out again shortly before smothering Luis Suarez's follow-up.

Those saves proved crucial as Arsenal snatched the win in the 91st minute, with Gabriel Martinelli picking out Havertz, who stood up to Silva to bend his low shot into the bottom-left corner.