Shkodran Mustafi was on target but we had to settle for a point from a challenging match on the road at Vitoria on Wednesday afternoon.
In a game of few clear-cut chances, and played in torrential rain, the hosts had the better of the first half and struck the post through Pepe, before Emi Martinez was called into action to make smart saves from Lucas Evangelista and then Edmond Tapsoba.
Unai Emery’s men were finding it tough to get a sight of goal, although Rob Holding – captain for this game – headed one over the bar before the interval, while at the other end Davidson curled an effort inches wide.
The team needed to change the momentum after the break, but it was Vitoria who had the first opportunity when Marcus Edwards was played in on goal but his cutback was cleared by Sokratis in the nick of time.
Holding went close again just after the hour mark with a header, but with the rain showing no sign of relenting, there was little to cheer the traveling Arsenal fans.
But with 80 minutes gone, Mustafi rose highest to meet Pepe’s free-kick and directed it into the far corner to put us ahead.
But there was to be one final twist when, deep into injury time, Bruno Duarte sent an acrobatic shot into the far corner to equalize.
What does the result mean
The Gunners still sit on top of the group with 10 points. Another win will secure qualification to the next face of the Europa League.
What next
Arsenal is back in Premier League action on Saturday when they travel to the King Power Stadium to take on Leicester.
Brendan Rodgers’ side is third in the table and has beaten us twice in our last three meetings with them. This match will be Unai Emery’s 50th Premier League match in charge.