Mikel Arteta hailed Arsenal’s achievement in reaching the Champions League quarter-finals for the first time since 2010 but warned they still have a “mountain to climb” if they are to win the competition.

Arsenal hauled themselves into the last eight with a 4-2 win on penalties over Porto at the Emirates, having levelled the tie with a 1-0 win secured through Leandro Trossard’s first-half goal. A tense and nervy 120 minutes of few clear chances went to the fire but two David Raya saves in the shootout meant the likes of Bayern Munich, Real Madrid and Barcelona are all potential opponents in Friday’s draw.

Related: David Raya the shootout hero as Arsenal battle past Porto and into quarter-finals

“So happy,” said a visibly delighted Arteta, who could barely wipe the smile off his face throughout his post-match media commitments. “It has been 14 years, which is a long time for a club like Arsenal and it shows how difficult it was. We really had to dig in to find the magic moment at the end. We’re starting to create an unbelievable energy in the stadium, we were all pushing to get it done and together we have done it.

“[The last eight] is where we want to be. We’ve been patient, worked so hard and a lot of people have made good decisions and showed courage in difficult moments and this is where you want to be.”

Arteta reserved special praise for Raya, who saved brilliantly from both Wendell and Galeno in the most eyecatching contribution of an Arsenal career that started nervously upon his arrival from Brentford in August. “David had some difficult moments at the start,” he said. “He has stood up with incredible personality and ambition and in the end he’s been rewarded.”

Players on both sides were out on their feet at the end of a tie that brought, in Arteta’s view, the best atmosphere he has experienced at the Emirates. “I’ve seen how they want it and want to sacrifice anything to win,’ he said of his team.

Asked whether a quarter-final berth made the prospect of a first Champions League title feel more realistic, Arteta opted to remain coy. “I think it’s still very far,” he said. “Now I’m going to sit at home, I’m going to look at the other teams we have to play and start another big mountain to climb.

Arteta offered “no comment” regarding an incident at the end of the match in which he exchanged words with the Porto manager, Sérgio Conceição, who appeared not to shake his hand.

His opposite number was rather more forthcoming, accusing Arteta of acting offensively during the game.

“The result was unjust,” Conceição said. “The team deserved to go through. What Arteta said, towards the bench in Spanish, he insulted my family. He should focus on training his team.”

Arteta is understood to have strongly denied the allegation after its emergence.