Image source, AFP

Don't these teams realise there is 45 minutes of football (at least) still to come?

It's become frantic, end-to-end, as Chelsea look to maintain their momentum while Lyon try to reassert control. Great stuff.

That Chelsea leveller was fully deserved - their response since going behind to that latest own goal has been exceptional.

They could easily have had two penalties and they have Lyon right on the back foot now. Chelsea will not want the half-time whistle to come.

Immediately following that equaliser, there was an ugly spat involving Chelsea's Ramona Bachmann and Lyon keeper Sarah Bouhaddi as the Blues forward tried to grab the ball and race back to the halfway line.

Both were booked and Bachmann has since been involved in a couple of meaty challenges.

She needs to be careful - Chelsea are back in this now, the last thing they need is a red card.

Chelsea win a free-kick right on the edge of the area as Delphine Cascarino fouls Erin Cuthbert. Chelsea are convinced it should have been a penalty. Fine margins.

Postpublished at 30 mins

30 mins

Chelsea 0-1 Lyon (1-3 agg)

Magdalena Eriksson is floored after a clash of heads with Lyon's Lucy Bronze.

The challenge earns Chelsea a free-kick on halfway, it finds Ji So-yun in the box and she shows quick feet but is quickly closed down by a gaggle of Lyon defenders.

Chelsea are still in this but they cannot afford to concede again. If Lyon get a second away goal, Chelsea would need to score four. Against the five-time European champions, that would surely be an impossible task.

The Blues are trying to find a response and Lyon's France captain Amandine Henry is booked for illegally halting a Chelsea break.

Elsewhere, Arsenal have sealed a first Women's Super League title since 2012 at the Amex Stadium by beating Brighton in front of a new WSL-record crowd of 5,265.

You can follow all the reaction here.

Own goals are threatening to tear apart Chelsea's season.

Magdalena Eriksson turned into her own net in stoppage-time of the FA Cup semi-final against Manchester City and did the same in the first leg in Lyon.

Now, Norway international Mjelde has caught the bug, although she could do little about it - Eugenie Le Sommer's shot just hit her leg. Such rotten luck for Chelsea.

Big penalty shout for Chelsea as a ball bounces up off Lyon defender Lucy Bronze's leg in the six-yard box and strikes her arm. It was not intentional but you have seen them given.

Superb header from Millie Bright to clear that corner with Ada Hegerberg lurking at the back post.

Chelsea have defended well - just as you would expect from a side that have conceded just 12 goals in 18 Women's Super League games this season.

Chelsea have resisted that initial surge from Lyon in the opening 10 minutes and are starting to come into the game. Just as I type that, Lyon break and earn a corner...

Love that Lyon have a player called Cascarino.

No relation to Tony, of course. His autobiography is worth a read, you know.

Whatever happens, British representation in next month's final is virtually assured given that England full-back Lucy Bronze is one of the first names on the Lyon teamsheet.

She's not had much to do so far this afternoon as Chelsea have spent most of the opening stages in their own half.

Image source, Rex Features

Lyon are looking dangerous early on, forcing a string of set-pieces, the latest a free-kick wide right after a Karen Carney foul.

Dzsenifer Marozsan's delivery finds the unmarked Amandine Henry but she heads over from a few yards out. Should have done better there.

First free-kick of the game goes to Lyon as Chelsea defender Magdalena Eriksson goes right through the back of Eugenie Le Sommer on the halfway line.

But Chelsea defend it comfortably. Busy start here.

Image source, AFP

And we're under way at Kingsmeadow. Lyon kick-off and launch it long but it's straight out for a Chelsea goal-kick.

As ever, you can have your say on today's action via #bbcfootball on Twitter.

Chelsea have named a completely unchanged squad from last weekend's first leg as boss Emma Hayes retains faith in the side that returned from France with that potentially crucial away goal.

Lyon, meanwhile, make one change as Welsh international Jess Fishlock drops to the bench and Amel Majri takes her place. England's Lucy Bronze starts for the visitors.

Chelsea: Berger, Ingle, Bright, Eriksson, Mjelde, Carney, Ji, Andersson, Cuthbert, Kirby, Bachmann.

Substitutes: Lindahl, Thorisdottir, Blundell, Carter, England, Spence, Engman.

Lyon: Bouhaddi, Bronze, Renard, Mbock, Bacha, Cascarino, Marozsan, Henry, Majri, Le Sommer.

Substitutes: Weiss, Buchanan, Simon, Kumagai, Fishlock, Jaimes, Van de Sanden.