Mikel Arteta’s side were aiming to continue their formidable league phase record when they hosted a Les Dogues outfit that had hardly relished their recent trips across the English Channel.
The Ligue 1 side were fortunate not to be a goal down inside the opening 20 minutes when Bruno Guimaraes fired his close-range shot wide from Jurrien Timber’s cutback.
Lille remained resolute in their shape and briefly stunned the Emirates crowd when Ayase Ueda fired home past David Raya, but Arsenal’s blushes were spared by an offside decision against Hakon Haraldsson in the build-up.
The Gunners were far from their best going forward, with their struggles epitomised when Mikel Merino blazed his strike well over the bar. It had been a positive opening 45 minutes for Davide Ancelotti’s visitors, but they could have conceded in first-half stoppage time had Berke Ozer not made a fine save to keep out an awkward shot from Guimaraes.
Arsenal were applying plenty of pressure on the Lille backline, and they finally got that elusive breakthrough in the 64th minute courtesy of a wonderful finish from Timber.
The Dutchman effortlessly took Madueke’s pass into his stride before applying a delightful dinked finish over Ozer to give the Gunners a deserved lead.
Eze then doubled their advantage three minutes later with a fine first-time finish from substitute Bukayo Saka’s cross, as the latter claimed an assist just two minutes after entering the pitch.
Two substitutes combined to make it 3-0 in the 71st minute, with Saka adding his name to the scoresheet with a cool finish from Kai Havertz’s cross to effectively extinguish any slim hopes of a Lille comeback.
Guimaraes was looking to add his name to the scoresheet, but was denied by Ozer, as Arsenal had to settle for three on the night.
This result means Arteta's side have now lost just two of their previous 32 group/league phase games (W26, D4), illustrating the ease at which they usually negotiate the first round of this competition.
Meanwhile, this defeat consigns Lille to a ninth successive away defeat in European competition against English opposition, leaving them pointless after two matches.
Flashscore Man of the Match: Jurrien Timber (Arsenal)