Just over a year since both sides last met in the semi-finals of the competition, the first leg of their latest encounter promised to be a thriller.
As it was 12 months ago, the French champions were the first to score. Jule Brand waltzed past the Arsenal defence before smashing the ball low into the bottom left corner. It was a stunning solo performance from the German.
The first five minutes were all Arsenal's, but Lyon turned up the tempo, and the Gunners were unable to deal with it.
It was becoming a very stop-start game, Lyon committing three fouls in just over a minute.
The biggest issue for Renée Slegers' side was the struggle to retain possession and create some opportunities for the frontline. Alessia Russo and Stina Blackstenius managed a combined 26 touches in the opening 35 minutes.
The hosts came close to restoring parity in the tie; Katie McCabe's cross was met by Caitlin Foord's header from close range, bouncing inches wide of the post.
Arsenal started the second half like the first, and managed their closest opportunity of the game so far when Olivia Smith fired into the side netting.
Just seconds later, Kim Little was taken out in the box by Wendie Renard, and despite the appeals of innocence, the referee awarded a penalty.
VAR intervened and ruled an on-field review, which saw the penalty overturned, much to the disappointment of the Emirates crowd. They didn't let that hamper them, though, as Smith had her effort from six yards out well stopped by Christiane Endler.
Lyon had been under heavy pressure in the opening 10 minutes of the second half, yet nearly doubled their lead through Korbin Shrader. The American midfielder fired over the bar from a tight angle.
Arsenal's pressure paid off, but it was an absolute howler of a mistake from Endler. Mariona's free kick bounced all the way through, where the Lyon keeper dropped the ball, and it ended up tapping the post and rolling in.
Ingrid Engen was judged to have got the final touch in her desperate attempt to prevent it crossing the line.
Much to the annoyance of the majority in the Emirates, there was a VAR check for offside, but the goal was awarded, which sparked large cheers.
For all their struggles in the first half, Arsenal came out flying in the second half, but Lyon's quality meant that chances would still arise, as one did for Kadidiatou Diani.
She raced past Lotte Wubben-Moy and smashed an effort off the underside of the bar, much to the relief of the Arsenal fans.
Foord had a lot of joy in the second half. Taylor Hinds clipped a ball into the left channel, giving the Australians lots of space to run into and forcing Endler into a save.
Arsenal needed a moment of quality to turn the game in their favour, looking no further than their record signing Smith. The Canadian is taking advantage of a horrible mix-up at the back from Endler and Renard, before tapping into an empty net.
It was a massive goal in the context of the tie, and Lyon will wonder how they let a result slip away with two huge errors.
Endler denied Foord once more, this time from range when a clawing right hand was required to stop the ball nestling in the bottom right corner.
With just six minutes of added time left to navigate, Arsenal retreated into a deep block, but Lyon were not causing massive problems for the Gunners.
It was a sensational second-half response from the European Champions, and one that had them 90 minutes away from Oslo.
They got a bit of luck with how the goals came about, but that came from perseverance, and Renée Slegers will be thrilled with how her side came out after half-time.