Qarabag's victory over Vorskla in Group E's other game meant a draw was enough to see the 'Gunners' progress, but injuries sustained by both Welbeck and Stephan Lichtsteiner meant that it came at a price.
Welbeck, Arsenal's top scorer in the competition since the start of last season, looked reasonably bright early on, but his evening was ended after just 28 minutes as he suffered a lower leg injury that saw him withdrawn on a stretcher after landing awakwardly.
Arsenal's fate was in their own hands before the game, with a win definitely enough for them to reach the last 32 and they started brightly on home turf, Sebastian Coates being forced to clear off his own line after a Matteo Guendouzi's low cross was diverted goalwards by a combination of Welbeck and Jeremy Mathieu.
Welbeck again threatened on 20 minutes as he flicked a free-kick from Henrikh Mkhitaryan, one of the brightest players on the pitch, wide of the far post.
However, the England man's night came to an abrupt end shortly afterwards as he landed in a heap after directing a header straight into the arms of Renan Ribeiro.
The hosts continued to have more of the ball, but barring a long-range Lichtsteiner effort that faded wide they looked like doing little with it.
Welbeck's replacement Pierre-Emerick Aubameyang almost broke the deadlock just minutes after the interval, driving an effort against the crossbar, but Arsenal's frustrating night continued.
The Gabonese later fired into the side netting after decent work from Alex Iwobi, before Lichtsteiner was also forced off with what looked to be a hamstring problem.
Mhkitaryan could have won it with 11 to play, but he couldn't generate enough power on his prodded effort from Iwobi's low cross and Ribeiro was able to make the save down to his left.
A late red card for Sporting's Mathieu did nothing to help Arsenal as the former Barcelona man was given his marching orders for scything down Aubameyang right on the edge of the box with just three minutes to play, only for the striker to blaze the resulting free-kick high and wide of goal.
The draw leaves Arsenal top of Group E with 10 points and certain of their place in the knockout stages. Sporting, meanwhile, occupy second with seven points.
November 8, 2018