Brilliant interception from Reece James and he quickly fizzes it down the line for Timo Werner.

Ruben Dias does equally as good a job to read the situation and gets across to deal with it.

N'Golo Kante and Kai Havertz link-up to keep the ball on the right. It's switched over to Mason Mount on the left but he's not quite on the same wavelength as Timo Werner.

City try to find Kevin de Bruyne on the edge of the Chelsea box but who's there to take it off him?

Kante, obviously.

N'Golo Kante makes football look easy.

Image source, Getty Images

Chris Sutton
Former Premier League striker on BBC Radio 5 Live

A good start to the second half by Man City, they are playing with more urgency.

Maybe Chelsea are happy to play narrower and allow crosses into the box because City don't have any real height up front.

Reece James robs it off Raheem Sterling but the City winger races back to prevent N'Golo Kante from kick-starting another Chelsea counter-attack.

Kyle Walker then curls it in from the right but it's easy for the keeper.

Kevin de Bruyne won't actually. He leaves it for Phil Foden and the young Englishman doesn't catch it.

N'Golo Kante picks it up inside his own area.

Raheem Sterling is fouled by Reece James. Free-kick to City on the left, which Kevin de Bruyne will curl in.

Former Chelsea player Joe Cole, speaking to BT Sport: "It is about composure now for Chelsea. They were solid first half, compact. Long way to go yet, it is a million miles until the end."

Rio Ferdinand
Former England defender on BT Sport

He [Pep Guardiola] is going to have to change something, we didn't see the City in the first half that we have seen.

I am intrigued by the tactical battle. Chelsea have the goal and can be sat there and be patient.

If the second half is as good as the first, we're in for a treat.

Off we go again!

A team has trailed at half-time in a Champions League final and come back to win the trophy on five occasions.

The last time a team came from behind to win their first ever European Cup or Champions League final was Porto in 1987.

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Rio Ferdinand
Former England defender on BT Sport

The pace of it was great, started like a house on fire but the goal. Kai Havertz's run was good but the ball from Mason Mount was absolutely on the money.

I think Pep Guardiola will change things for the second half.

Celebrations in the ground...

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... and in London....

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Sneaky Jose: Need to put De Bruyne back into midfield, he looks lost as a false nine.

Abdul Karim: Pep should have known better!! You can't use Sterling in Europe!

Phil McNulty
BBC Sport chief football writer in Porto

Chelsea fans in buoyant mood as the teams go off at half-time and rightly so as their team fully deserves their lead.

Thomas Tuchel has got his team playing right on the front foot while Manchester City look flat and very nervous at the back.

Much talk of Pep Guardiola deciding to dispense with the protection and solidity of the likes of Rodri and Fernandinho - and there will be a lot more if they don't pull this around.

Chris Sutton
Former Premier League striker on BBC Radio 5 Live

Chelsea deservedly lead, they have ben the better team with the bigger chances, Timo Werner missed a couple of chances he should have gobbled up but they got their goal later on.

Thinking to do for Pep Guardiola, a huge second half for Manchester City.

It was a stunning half of football, a frenetic start and Chelsea carved the opening just before half-time, Kai Havertz took his goal really well, the vision and weight of the pass from Mason Mount was perfect - it was all about the pass.

Thomas Tuchel and his team have played a blinder.

Not a bad time to score your first goal in the Champions League.

Image source, Getty Images

Image source, Getty Images

Image source, Getty Images