Full-time: Paris Saint-Germain 1-3 Barcelona
Full-time: FC Porto 3-1 Bayern Munich
What an evening of Champions League football.
The brilliance of Luis Suarez gives Barcelona what should be an unassailable lead to take back to the Nou Camp on a night to forget in Paris for a half-fit David Luiz.
But the main story undoubtedly comes from Portgual's second city, where Porto pressed high and showed no fear to earn a two-goal victory over a Bayern Munich side who lacked direction and a sense of urgency.
The Bundesliga leaders were very poor indeed after the break and will have to work hard to overturn that deficit on their own turf in a week's time.
That is all we have time for tonight, join us again soon.
Paris Saint-Germain 1-3 Barcelona
FC Porto 3-1 Bayern Munich
A chance for Barcelona as Messi, looking for his 400th Barcelona goal, bends in a free-kick that is dealt with by Sirigu.
Porto still holding firm in the dying seconds.
Panic amongst the Barcelona defence as Ezequiel Lavezzi appeals for a penalty after being felled by Adriano.
Nothing given, though, and Cavani's follow-up is blocked by a determined Mathieu.
A lifeline for PSG as Van der Wiel's goalbound effort is deflected past Ter Stegen by substitute Mathieu.
3-1 in both games. A refreshing tonic after last night's cagey affairs.
Goal: Paris Saint-Germain 1-3 Barcelona (Gregory Van der Wiel)
PSG's stellar home record in European competition is about to come to an abrupt end as Suarez notches his second and Barcelona's third.
The former Liverpool talisman plays a neat one-two with Mascherano, nutmegs Luiz for a second time before beating Sirigu with a fantastic strike into the top corner.
Goal: Paris Saint-Germain 0-3 Barcelona (Luis Suarez)
A similarly jinking run from Messi sees him ease past four struggling defenders before shooting wide of Sirigu's right-hand post. A third goal for the visitors really would put this tie beyond reach.
A great goal from Suarez as he nutmegs the helpless David Luiz and holds off the challenge of Maxwell to beat Sirigu and extend Barcelona's lead.
Cavani responds with a fierce effort that requires a strong save from Ter Stegen.
Goal: Paris Saint-Germain 0-2 Barcelona (Luis Suarez)
Porto extend their lead through captain Martinez after a long ball forward was badly misjudged by Boateng.
The Colombian shows good composure to round Neuer and squeeze the ball home from a difficult angle for his sixth goal in seven Champions League appearances this season.
Substitute Sebastian Rode tries to respond immediately but his shot is saved by Fabiano.
Goal: FC Porto 3-1 Bayern Munich (Jackson Martinez)
A golden chance for Porto as Neuer makes a superb save to deflect Casemiro's strike on to the bar.
A second shot on target in quick succession for PSG, this time Adrien Rabiot sees an attempt comfortably saved.
Worried looks from the Barcelona bench as Iniesta goes down once again following a collision with Pastore and grimaces in pain.
The stretcher is brought on and Xavi is preparing to enter the fray.
Javier Pastore signals PSG's intent with a low shot that bounces awkwardly in front of Ter Stegen. The German parries the ball away to safety.
The players are back out at both the Estadio do Dragao and the Parc des Princes. Second-half updates to follow.
Bayern have recovered after a truly shocking start, but Porto should not be too disheartened at having conceded that away goal.
PSG, meanwhile, have it all to do after a tame first-half in which their only real threat came on the counter attack.
Paris Saint-Germain 0-1 Barcelona
FC Porto 2-1 Bayern Munich
Cabaye swings in a deep cross for Cavani, who sends an acrobatic effort wide but again is adjudged to have strayed offside.
The half-time whistles sound.
A moment to forget for David Luiz as he is robbed in possession by Suarez and can only watch on in horror as the Uruguayan bends a shot on goal. Sirigu saves, but looks to have injured himself in the process.
Meanwhile, Casemiro heads over for Porto.
Iniesta receiving treatment after a hefty challenge from Cabaye but it looks like he will be able to continue.
Another chance for Cavani, who meets a cross from the left but can only send his shot into the grateful arms of Ter Stegen.
Cavani left all alone to head wide from a free-kick but the linesman on the far side is flagging for offside.
Porto hit the bar after a floated cross-cum-shot from Alex Sandro proves difficult to handle for Neuer.