That's all for this live page with Arsenal losing and being left with work to do in the second leg if they are to move into the Champions League quarter-finals.

Thanks as always for joining us and for all your comments. From all the team here, thanks and see you next time.

Image source, EPA

Marissa Thomas
BBC Sport

Image source, Getty Images

Arsenal were stunned as Galeno scored in stoppage time to give Porto the advantage from the first leg of their Champions League last-16 tie.

The Brazilian winger took a few touches to set himself before curling a wonderful finish into the net, past the despairing full-stretch dive of David Raya.

Sergio Conceicao's home side should have been ahead at the break after Galeno hit a shot off the post and somehow put the rebound wide.

That was a huge let-off for Arsenal, but Galeno made no mistake in the closing stages.

Nico Gonzalez's powerful strike had earlier sailed over the bar as the home side tried to open the scoring in the first half.

The Gunners dominated possession but failed to have a single shot on target in the match, with William Saliba and Kai Havertz heading wide from corners.

The second leg will take place at Emirates Stadium on 12 March, when Arsenal will aim to reach the quarter-finals for the first time since 2009-10.

Adam Millington
BBC Sport

Image source, Reuters

Victor Osimhen salvaged a draw for Napoli in his first club appearance since December as they held Barcelona in their Champions League last-16 first leg.

Robert Lewandowski handed Barca the lead in the 60th minute in Italy when he arrowed an effort into the bottom corner from the edge of the area.

Barcelona were dominant against a Napoli side whose final-third efforts were often lacking in Francesco Calzona's first game in charge.

But the hosts eventually found a way back when Osimhen slipped past his marker in the box before rifling past Marc-Andre Ter Stegen to level. The second leg takes place in Barcelona on 12 March.

Osimhen was part of the Nigeria side which lost to Ivory Coast in the Africa Cup of Nations final in February and missed his side's most recent league game through suspension.

The visitors had the brighter start with 16-year-old Lamine Yamal - who became the youngest player to feature in the Champions League knockout stage - making inroads on the right-hand side.

• This is just the second time on record (since 2003-04) that Arsenal have failed to record a shot on target in a Champions League game, previously doing so away to Barcelona in the last 16 in March 2011.
• Arsenal have failed to score in a Champions League game for the first time since a 2-0 defeat to Barcelona in February 2016, ending a run of 15 consecutive games with a goal (37 in total).
• Arsenal are just the fifth side to lose five successive knockout-stage games in the Champions League, after Roma in February 2018, Bayer Leverkusen in March 2014, Celtic in March 2013 and Real Madrid in February 2010.
• Porto’s Galeno has been involved in more goals than any other player in this season’s Champions League (eight - five goals, three assists). At 93:22, his strike was their latest winner on record in the competition (since 2003-04, excluding extra time).

Theo Walcott
Former Arsenal forward on BBC Radio 5 Live

I've said this numerous times recently, I think the argument about Arsenal's lack of prolific goalscorer will rear its ugly head again.

I am a big fan of a certain Brentford forward that I won't name... But it is one of those. Arsenal are a really big team, but with all the set pieces, if you've got someone like that in your team you are an even bigger threat.

There was no Gabriel Jesus tonight, so Arsenal didn't really have anyone else to call upon. Kai Havertz as good as he has been recently, he is not a striker either.

That is something that Edu and Mikel Arteta will be discussing in the summer, there is no doubt about that.

• Barcelona have progressed from each of their last 20 two-legged knockout stages in the Champions League when avoiding defeat away from home in the first leg, in a run dating back to the 2005-06 campaign.
• Since the start of the 2019-20 campaign, Barcelona forward Robert Lewandowski has been directly involved in 18 goals in 12 appearances in the Champions League knockout stages (12 goals, six assists) – only Karim Benzema (19) has been involved in more such goals in this period.
• Napoli’s Victor Osimhen has scored six goals in his last six games at the Diego Armando Maradona in the Champions League. Since the start of last season, the only players to score more goals at a specific venue in the competition are Erling Haaland at the Etihad (12) and Kylian Mbappe at the Parc des Princes (nine).
• At the age of 16 years and 223 days, Barcelona’s Lamine Yamal became the youngest ever player to appear in a knockout stage game in the Champions League. Indeed, the only two 16-year-olds to start a match in the knockout stages of the competition both have done so this season (Yamal and Paris St-Germain's Warren Zaire-Emery).

Arsenal

Arsenal midfielder Declan Rice speaking to TNT Sports: "When it's 0-0, you look up at the clock and it's 93 minutes gone, if you aren't going to win the game then don't lose it. Maybe have the bit of savviness about us to stay in and get a draw in a tough stadium against a tough opponent. A lot to play for in the second leg."

On conceding so late in the game: "There were a couple of giveaways on the edge of our box. They caught us on the counter and he's stuck one in the top corner which is really disappointing. We're really positive as a group, we've had such a good start to 2024 that we're not going to let this get us down. We'll address this game."

On why it was so difficult to create chances: "They know what they're doing. Porto are a really honest, hard working side with great players. We have to change our approach in the home leg and give it absolutely everything. Even though we're a goal down it's a nice goal to aim for when we can change it around in the home leg."

On the approach for the second leg: "I think it's about keeping our heads. It's hard to concede that leg. Knowing how we play at home, with our fans and energy, I think you'll see a team on the front foot from the start and we'll be looking to do that."

On what to take from the defeat: "You don't know what to expect, you can't overlook anyone ever because it's the Champions League. It's a real kick in the teeth because we've conceded late but we know what to do. We're not going to let our heads drop, it's about getting back, recovering, going again in the Premier League, and we'll be ready again for the Champions League for sure."

Arsenal

Arsenal manager Mikel Arteta, speaking to TNT Sports: "We have to manage much better. We cannot win with the way we handled the ball on three occasions in deep areas. If you want to be in the quarter-finals you have to beat your opponent and this is what we will have to do at the Emirates now."

On what Arsenal were lacking: "We lacked threat. We lacked aggression, especially with the ball in the final third. We can do better."

On whether Porto made it difficult or it was down to Arsenal's shortcomings: "I think it's a team that's very well-organised defensively and they break your rhythm all the time. There are certain things we will have to do much better, we know what to expect."

On struggling with set pieces: "We couldn't even touch anybody because everything was a free kick. We will learn from that, prepare better, and go and do it."

Theo Walcott
Former Arsenal forward on BBC Radio 5 Live

Image source, Getty Images

We were speaking about the squad depth that Arsenal have before the game, but now looking back, does Mikel Arteta trust the players outside of that starting XI? He only made one substitution tonight.

It could have been a game where he decided to shut up shop even more and brought off the likes of Gabriel Martinelli and Bukayo Saka, who were not as effective as they could be tonight.

As a coach would you feel that you could just shut up shop and take the 0-0 back home to the Emirates?

Former Arsenal defender Martin Keown on TNT: "The handbrake was on a little too much, was that inexperience? They need to hold that hurt now. Porto contained Arsenal."

Neil Lennon
Former Celtic manager on BBC Radio 5 Live

Image source, PA Media

With less than a minute to go you have to be smarter than that, keep hold of the ball. Instead of keeping the ball Gabriel Martinelli tries to smash a long diagonal to Bukayo Saka and which left Arsenal a bit open.

The ball gets to Galeno, Arsenal don't get out to him quick enough, probably for the first time in the entire evening.

But I also have to question the keeper, the ball almost goes over him rather than past him, he was too far out of his goal when Galeno hit the shot.

You have to admire the doggedness from Porto. They set up to nullify Arsenal and they did that, and it was a smash and grab at the other end.

Jonny: Keown - "sucker punch." Really? Arsenal didn’t have a shot

David: How can Arsenal complain about Porto when they can’t muster a shot on goal. The object is to score and Porto did that much.

This is how it stands going into the second legs, which will take place between 5-13 March.

Image source, .

Theo Walcott
Former Arsenal forward on BBC Radio 5 Live

These ties aren't won over one leg. I've been in this situation before, you've gone to a situation like this and not got the result that you want.

But I am confident that given Arsenal's overall form at the moment and the atmosphere in the Emirates, they will still be able to go through quite comfortably.

I don't think the second leg will be as tight as this, I think it will be open and Arsenal will get through.

Arsenal failed to register a shot on target in this game, it's the first time they failed to have a shot on target in a game in the Champions League since facing Barcelona on 8 March, 2011.

Neil Lennon
Former Celtic manager on BBC Radio 5 Live

Image source, Getty Images

I don't think Arsenal did a lot wrong and I don't think 1-0 will be enough for Porto going to the Emirates.

You have to credit Porto, they had an excellent defensive structure, worked really hard, Arsenal matched them in those areas to be fair.

At 0-0 there is always that potential for a deflection or a wonder goal like we've seen tonight. It was a wonder strike from Galeno.

It is a "sucker punch", says former Arsenal defender Martin Keown on TNT. "Maybe it comes down to experience, I hope it doesn't come back to haunt them.

"Arsenal are still very much in this tie."