Henrikh Mkhitaryan limps off, he didn't really recover from that tackle a minute ago.

Alex Iwobi is on to replace him. It feels like a long time since he was flavour of the month.

Image source, AFP

Lazio regain the lead!

Marco Parolo breaks from midfield and scores from another well-worked Lazio move with deft flick.

That's Lazio's 300th goal in Uefa competitions for what it's worth.

Image source, Reuters

Down he goes. Arsenal midfielder Granit Xhaka dives in on Aleksandr Golovin. Booking.

No Arsenal players are one yellow card away from missing the second leg.

Now CSKA's Georgi Schennikov is booked for clipping Henrikh Mkhitaryan.

CSKA Moscow are showing why most teams don't play a back three whose combined age is well over 100. Arsenal are picking them apart at will.

Aaron Ramsey is close to his third goal - again.

Henrikh Mkhitaryan's shot is saved, Jack Wilshere can't get onto the rebound and Ramsey volleys over from 10 yards out.

Image source, Reuters

Aaron Ramsey goes close to his second hat-trick of 2018. Nacho Monreal's cross finds the Welshman, but his shot hits Sergei Ignashevich - it could go anywhere, but it goes wide.

Image source, AFP

Good punch by Petr Cech to clear from a corner, Alexandre Lacazette starts a break and Ahmed Musa hacks him down. Yellow card.

Half-chance for Arsenal as a CSKA defender miscontrols the ball off Shkodran Mustafi, who wasn't expecting it, and the ball bobbles wide.

Mesut Ozil plays an absolute dreamboat of a defence-splitting pass over the top for Henrikh Mkhitaryan, who takes a touch but then kind of stubs the ball wide.

Image source, Reuters

Ricky: This is Arsenal, I might put a pound on the game finishing 4-4.

Anon: I am reading the comments on the Arsenal lead and as a longstanding fan I am not confident at all. This is NOT all over by any means. We have been here before.

I have no idea what's going to happen in this half. But I'm looking forward to it. 8-2?

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Simon: It would seem Aubemayang giving Laca that pen has worked out well

Daniel: Dunno why we signed Aubameyang in January, Lacazette seems to be doing the biz and should be the main man upfront!

Alexandre Lacazette has scored 10 goals in his last 13 Europa League appearances, with these his first two as an Arsenal player in the competition (eight for Lyon).

Mesut Ozil has assisted four goals in his last three Europa League appearances for Arsenal (two at AC Milan and two this evening).

Image source, Getty Images

Kyle: When Arsenal are on form going forward they are still a joy to watch. If it isn't over yet you get the feeling Arsenal will have the tie all but won by the end of the night.

Harrison: If my team were playing against a 38-year-old and two 35-year-old centre-backs, I'd hope we'd be up by three goals too..

Marseille's makeshift defence finally gives in to Leipzig's attacking might.

Timo Werner capped off a speedy Leipzig counter attack, cutting in from the left and firing low underneath stand-in goalkeeper Yohann Pele.

Olorunda: The best thing to do when your opponent scores an away goal is to beat them silly in order to render the goal useless, well done.

Gbade: Arsenal are playing really well and a pass to the semis looks assured now.

Tabyeesh: If Giroud’s goal was a scorpion, what is Ramsey’s? A dolphin? A grasshopper? A frog?

The referee takes mercy on CSKA Moscow. No injury time.

He's been quiet tonight, but give him space at your peril.

Antoine Griezmann capitalises on another Sporting blunder, with former Barcelona defender Jeremy Mathieu missing an interception and leaving Griezmann one on one. He doesn't miss those.

Image source, AFP

Arsenal think this is some kind of showboating YouTube video. Granit Xhaka pings a ball over the top and Mesut Ozil shoots first time with the outside of his boot - but it's over the bar.

Nice to watch, but maybe should have taken a touch and shot normally.