No effort on goal for about five minutes - quite something in this tie. Dortmund are seeing more of the ball, with sub Ousmane Dembele keen to run at the home defence. Beware of the counter. Monaco are ready to suck the Germans in like an alligator waiting for a turtle.

We are getting a lot of tweets giving Barcelona stick for diving, moaning and generally being bad losers. They do not like it up 'em.

Ousmane Dembele on, Erik Durm off for the Germans. Like his namesake at Celtic, Dembele is a wonderkid forward. It was half-surprising that the 19-year didn't start.

Barca are frustrated - Neymar in particular gets testy with the referee and has to be told to calm down. The hosts have had more efforts on goal, but Gigi Buffon is yet to get his gloves dirty.

Image source, Reuters

Just because Juve are sharp as a knife going forward, it doesn't mean that the back door is any more unlikely to be left unlocked. When Barca swarm, the Italians are organised. Bank of five, bank of three in front. Old habits die hard.

Jme Atkins: I love watching Monaco. It'll be such a shame when this team is taken apart. Better version of Spurs.

Even Thierry Henry couldn't manage this....

Kylian Mbappe is the first player to score in each of his first four Champions League knockout games.

And here's another beauty, stat fans.

The 18-year-old Monaco forward is the youngest player in Champions League history to score five goals, 41 days younger than Real Madrid legend Raul.

Image source, Getty Images

Juventus might have set off like a steam train in the Nou Camp, but they have been slowed down by Barcelona.

Barcelona are now dominating possession, as you can see in our graphic below, and starting to set up camp in Juve territory.

Image source, Opta

Don't move. Don't breathe. Don't take your eyes off these two games. Now it's Barca's turn to threaten, Lionel Messi shanking a left-footed effort from 12 yards out. A trickle past the post when you'd expect the great man to hit the target.

Image source, AFP

Off the post! Nuri Sahin rattles the home woodwork with a wonderful, dipping, arcing free-kick. Over the wall, keeper flying in a desperate attempt to get across, ball rattling back off the timber.

Image source, Reuters

These are two excellent games, both end to end, helped by the fact that two sides know they have to keep pressing just to have a sniff of getting back into their respective ties.

Combined number of goals tonight? 10 plus...

What. A. Challenge. Gerard Pique just about keeps pace with a breaking Juan Cuadrado and slides to stop the pass finding an open Paulo Dybala. Juve are all over Barca, who are having to commit waves forward in a bid to get back into this tie.

Juve haven't come to hold what they've got. In the first 12 minutes the Old Lady have had 62% of possession. They know if they score one, Barca have got to get five. Gonzalo Higuan! Shot from outside the area as the ball dropped, flashing over the bar. Probably should have hit the target.

Image source, Getty Images

That has made Dortmund's mountain a little higher. They now need to score three unanswered goals in they are to stop Monaco reaching the semi-finals for the first time since 2004.

Good lord, it's already end to end. What price is more than four goals?

Slightly later than billed, it's under way in Monaco.