Click audio icon to follow 5 Live Final Score and live commentary
Mount's superb turn and shot for Chelsea lead over Porto, Chilwell rounds keeper for second
Second leg also in Seville, Spain - this was Chelsea's 'away' leg, away goals rule still used
Bayern's Choupo-Moting & Muller wipe out PSG's two-goal lead given by Mbappe & Marquinhos, but Mbappe gives PSG edge
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Jon Connor: Bayern sorely miss Lewandowski. Couldn't see past the Germans when draw was made. PSG have surprised me.
Ted Clarke: Mason we love you, Mason we do! Fantastic and totally underrated player and still with years ahead of him to rise even higher. Lampard, Tuchel and Southgate can’t all be wrong.
Porto 0-1 Chelsea
Otavio's free-kick is headed to Corona, who hits a sweet volley which Cesar Azpilicueta turns behind for a corner.
Porto 0-1 Chelsea
Chelsea's Kai Havertz clips Otavio, who lands awkwardly and hurts his groin I think. But he's OK. Free to Porto.
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Another one of those games that shows you how little early season predictions count for. Conventional wisdom a few months ago was that Bayern were nailed on for the Champions League, now look.
Dan
Everything crossed for Poch and PSG. I'm sure all Spurs fans are willing him on. I just hope and pray he doesn't come knocking on the door for Kane or Son next season.
Trevor, Surrey.
Porto 0-1 Chelsea
Zaidu Sanusi - who is an attacking left-back for Porto - blasts in a cross but it's too powerful for anybody to control and Chelsea get it away.
Porto 0-1 Chelsea
Clinton Morrison
Former Republic of Ireland striker on BBC Radio 5 Live
If I'm Porto's manager, I'm disappointed in my goalkeeper - your hands are there to save it. It was so poor, the ball was right beside him, so he knows as keeper he has to do better.
What do Porto do now? Do they still come out? Would they take this result and wait until the second leg when two of their crucial players are back? It's a different game then.
Eric Maxim Choupo-Moting (37 mins)
Bayern back in it!
PSG will be kicking themselves at this though because it is a free header for Eric Maxim Choupo-Moting, who powers home from the middle of the box.
A third goal in this game and there's absolutely going to be more with the way these two sides are playing.
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Lewis Chapman: That is just world class from Mount, wow, I don't understand how there are some people who doubt him, absolutely love the man.
Rachel T: Spurs fan here - Mason Mount is quality. On and off the pitch.
Porto 0-1 Chelsea
That was Mason Mount's first Champions League goal. He becomes Chelsea's youngest ever goalscorer in a Champions League knockout match (22y 87d).
Bayern Munich 0-2 PSG
Neymar has been excellent so far. He now has 25 Champions League assists, the most of any player in the competition since his debut in 2013-14.
The Brazilian has also been directly involved in 67 goals in 66 Champions League appearances (41 goals, 26 assists).
Porto 0-1 Chelsea
Porto keeper Agustín Marchesín tried - and failed - to save the ball with his legs.
Porto 0-1 Chelsea
Clinton Morrison
Former Republic of Ireland striker on BBC Radio 5 Live
He's the go-to man for Chelsea. He's the go-to man for England. It's patient play and even though Porto have a good shape, it's a good ball in by Jorginho into Mason Mount's feet. The turn is so sweet, so sharp. The goalkeeper is at fault for me, though.
Bayern Munich 0-2 PSG
Bayern just cannot cope with the pace of the PSG attack as Neymar charges through the middle before a last-ditch challenge comes in just as he was about to have a go at goal.
The hosts make a change as they look to try and find a way back into this. Alphonso Davies is on for Leon Goretzka.
Porto 0-1 Chelsea
That was Chelsea's first shot in a Champions League quarter-final in seven years.
Bayern Munich 0-2 PSG
Marquinhos appears to have injured himself after scoring because he's having to go off. Ander Herrera is on in his place.
Mason Mount (32 mins)
Chelsea take the lead and it's that man Mason Mount.
Jorginho plays a wonderful through ball to Mount, who spins - leaving Zaidu Sanusi on the ground - before controlling it and rifling into the bottom corner.
Porto 0-0 Chelsea
Clinton Morrison
Former Republic of Ireland striker on BBC Radio 5 Live
You have to credit Porto. Tactically, they have got it spot on at this moment.
But if I'm Timo Werner, I need to stretch the pitch and make runs, because if I stretch the pitch, it allows key players like Mason Mount and Kai Havertz to get on the ball and cause problems. At the moment, these players are not in the game.
Porto 0-0 Chelsea
Reece James pulls the ball back to Jorginho who overhits his pass into Ben Chilwell on the left.
Porto 0-0 Chelsea
Reece James has a cross cleared. And how much am I wishing I was covering the other game instead?
Marquinhos (28 mins)
PSG have a second!
This is brilliant from Marquinhos as he picked out inside the box by a superb ball from Neymar and the defender controls with one touch before producing a striker's finish with his second.
Incredible scenes. PSG are flying.