Conceicao was involved with an altercation on the pitch with Arteta at the end of the game, and gave a terse explanation of what was said.

"During the game, [Arteta] turned to the bench and in Spanish - it must be a Spanish coach thing because it was the same thing with [Pep] Guardiola - he insulted my family," he said.

• Arsenal 1-0 Porto (1-1 on agg, 4-2 on penalties) - Match report
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"In the end I told him to pay attention because who he insulted is no longer with us, and to worry about coaching his team, because due to individual quality he has an obligation to do more and better."

Arsenal sources have strongly denied any offensive or insulting sentence towards the Porto manager and Arteta has refuted the allegations.

"No comment. Thanks very much", was the reply from the Gunners boss when asked about Conceicao's accusation.

Arteta hails 'magic night' for Arsenal

The altercation came at the end of a dramatic evening at the Emirates as Arsenal beat Porto 4-2 on penalties to reach a first Champions League quarter-final in 14 years.

Trailing 1-0 from the first leg in Portugal, a goal from Leandro Trossard just before half-time levelled the tie late in the first half, but there Arsenal's momentum stalled as they failed to wrap the game up inside 90 minutes.

After a nervous extra-time it took heroics from goalkeeper David Raya, saving twice in the shootout, to put the hosts into the last-eight for the first time since Arsene Wenger's team faced Barcelona in 2010.

"A magic night," said Arteta. "We expected a really tough opponent. It's very difficult to generate momentum and that's credit to them.

"It's a huge experience for us. We had to do it as well through penalties. Credit to David who had some difficult moments to start but showed incredible determination and stood up and got rewarded."

Raya was the hero, saving from defender Wendell and first-leg match-winner Galeno to send Arsenal through.

"For [the players] to do it when the club hasn't done it for 14 years, I tell you it will be a boost," added Arteta. "The margins are so small.

"I see how much they want it, how much they try and they are able to sacrifice anything to win. When you play like this at the end good things are going to come your way.

"It's another big step [in the season], especially as a club. For seven years we haven't been in this competition and for 14 years we haven't got this far. That tells you the difficulty of it. We want more and we're going to go for it that's for sure.

"It's the first time that I've done it in the Champions League. I try to learn every day, get advice and that's why you have good people around you, great coaches around you as well to help you and make you better."

Raya: It means everything

This was only the second time Arsenal were taken to extra-time in a Champions League match, and first since the 2008-09 last 16 against Roma, which they also progressed from after a penalty shootout.

"Obviously it's a great feeling, especially for me personally - my first time in the Champions League and the first time in a long time club has got to the quarter-finals," Raya told TNT Sports.

"We've been working a lot on penalties this year because on a night like this you need to be good and the hard work has paid off. It's a great night.

"I should have saved three, but I'm over the moon to save two and get through to the quarter-finals.

"Porto made it so difficult over there and here. But we scored the goal that we needed and it went to penalties. Obviously, mentally it's tough but the team played really, really well, we kept a clean sheet, scored the goal and went to penalties.

"It means everything, You play football for these kind of nights. Over the moon and I'm going to celebrate and enjoy the night."

"You are very nervous. You are hoping for the best but you know it's a bit of a lottery. We did our preparation yesterday and the day before just in case and it really helped so credit to the goalkeeping coaches as well.

"We have started to create an unbelievable energy in the stadium and we are all pushing to get it done, and together we've done it. Unbelievable. That's where we want to be. We have been patient and this is where we want to be."

Bukayo Saka, who scored the third penalty, was thrilled to get through.

"I'm buzzing, we're going through and I'm so proud of the team," he said. "To win on penalties is great for the spirit. I prepare myself, practising penalties so I was more than ready. Just pleased to see it go in."

England winger Saka immediately set his sights on the potential title decider at Manchester City next.

"Right now we're top of the league and in the quarter-finals of the Champions League so that gives us confidence that we can go to the Etihad and get a result," Saka added.

Arsenal end their round of 16 hoodoo - Opta stats

• Arsenal have progressed to the quarter-final of the UEFA Champions League for the first time since 2009-10, ending a run of seven consecutive last 16 eliminations in the competition.
• This was the first UEFA Champions League knockout match to go to a penalty shootout since the 2016 final between Atlético Madrid and Real Madrid.
• Porto have been eliminated from each of their last eight major European knockout ties against English opposition since knocking Manchester United out of the 2003-04 UEFA Champions League last 16.

What's next?

Arsenal must wait nearly three weeks for their next game after the postponement of their Premier League home fixture against Chelsea due to the Blues' FA Cup participation this weekend, which is then followed by an international break.

The Gunners return to action with a huge title clash against Manchester City as Mikel Arteta's side go to the Etihad Stadium on March 31; kick-off 4.30pm, live on Sky Sports.

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