Talisman Willian looks the man most likely to get a goal for Chelsea and he does superbly to arc in from the left wing, beat a man and hit a low shot which Kevin Trapp pushes clear. Eden Hazard collects the loose change and hits a shot which Trapp pushes out and the offside flag then belatedly rises on the far side.

Twenty-five to go...

Phil McNulty
BBC Sport chief football writer at Stamford Bridge

The sight of Diego Costa limping off on the hour has temporarily subdued Stamford Bridge. Not only did he get Chelsea's goal but he really looked in the mood tonight.

Bertrand Traore is handed the big responsibility with Chelsea needing a goal but Guus Hiddink has lost his main man there.

Martin Keown
Former Arsenal defender

"Laurent Blanc was very magnanimous there, lots of sportsmanship there you don't usually see. 

"It was sad to see Costa go off as he's been excellent tonight. Traore scored a great goal from outside of the box against Stoke on Saturday, he may need to do the same tonight."

Almost curtains for Chelsea as the impressive Adrien Rabiot nicks the ball in a dangerous area and feeds the ball into the path of Zlatan Ibrahimovic. He's wide on the left and hasn't got the pace to surge away from Gary Cahill, instead he pokes a low left-footed shot at the near post and it's pushed away...

Image source, Reuters

How big a blow is that injury to Diego Costa to Chelsea's chances? They have half an hour to score at least once without him...

Bertrand Traore is on - but I didn't expect him to replace Diego Costa!

Costa was immense at times in that first half but he looked to be struggling with a calf injury. Loic Remy slides further down the list of forwards...

Image source, Reuters

Nice, neat football from Chelsea now but PSG are well set, they are not leaving any space in behind and the blue shirts have to pop it square instead. Pedro takes a touch but drags a poor shot wide from 25 yards. Bertrand Traore looks like he is coming on. 

Martin Keown
Former Arsenal defender

"If Chelsea get the next goal they will have the ascendency, the crowd haven't woken up in the second half yet. There's some real class on show from both sides."

PSG will be very happy with this opening 10 minutes to the second half. Laurent Blanc's men edging towards the last eight. Unless. Unless Chelsea can breach their defences. Diego Costa chips the ball home beautifully but the flag was up - JUST offside...

Well! Everyone stops as Blaise Matuidi fouls Willian on the edge of the box, but referee Felix Brych just allows play to go on. Chelsea are caught short and Lucas bursts forwards - danger here! - and Mikel takes one for the team and chops him down. A stonewall booking.

The free-kick is poor though and Chelsea survive.

A second goal for PSG would rule out extra-time...

Postpublished at 50 mins

50 mins

Chelsea 1-1 PSG (Agg: 2-3)

Dead leg alert! It's up there with being winded or stubbing your toe on a hard surface isn't it? Horrible.

A PSG knee goes right into the thigh of Eden Hazard and that will hurt for a good 12 minutes or so.

Martin Keown
Former Arsenal defender

"Much better from Chelsea, they've had a slow start to the second half but Willian is doing extremely well."

That's more like it from Chelsea as Willian skips away down the left, he is lightning quick, his pull-back is good for Diego Costa and his shot is well blocked by a sprawling David Luiz. He gets his fair share of grief, Luiz, but that was excellent... 

Image source, Reuters

Chelsea start the half sitting 10 yards off of PSG and Martin Keown is far from happy about it. He wants the Blues to come out and test the visitors high up the pitch from the off. 

Phil McNulty
BBC Sport chief football writer

"Chelsea have shown real drive and character to fight their way back into this Champions League tie after being pushed right on to the back foot by Adrien Rabiot's goal.

"They have pressed PSG's defence into uncertainty and can enter this second half with real hope. It is a performance that has also enlivened Chelsea's fans, who must have feared the worst when PSG struck with that early goal."

Here we go...

Here come the players at the Bridge then. Forty-five minutes to go, will Chelsea be in or out?

Should Chelsea need to change it from the bench, they have Oscar, Loic Remy and youngster Bertrand Traore available. 

Give it 10 minutes and see?

England play their final game of the SheBelieves Cup at 22:00 GMT. They take on France in a battle to avoid the wooden spoon, having lost to hosts USA and Germany in the round-robin tournament.

You can watch the game on BBC Red Button and online, as well as follow live text commentary from 21:30 GMT.