Porto manager Sergio Conceicao claimed Arsenal boss Mikel Arteta insulted his family during the London club's penalty shootout win over the Portuguese side in their dramatic Champions League last-16 tie.
Arsenal won 4-2 in the shootout following a 1-1 draw on aggregate, booking their place in the quarter-finals for the first time since 2010.
Tensions were running high at the Emirates and the managers were seen having a heated conversation at the end of the game.
"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," said Conceicao.
"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."
When asked about the incident in his post-match press conference Arteta said: "No comment."
The Gunners manager savoured a "magic night" after his side dug out a hard-fought win.
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 shoot-out, 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.
"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."
Reporting: Reuters/PA
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