Atletico were beaten 3-2 in North London on Wednesday night, but their dominant 5-2 win at the Riyadh Air Metropolitano in the first leg proved decisive. It was enough to send Simeone's side into the last eight, where a huge test now awaits.

Simeone admitted his pride after the result, but made it clear the challenge ahead would be even tougher. Atletico will face FC Barcelona in the Champions League quarter-finals in April.

"It is a time to be happy," he said. "As a club and as a team, we are delighted for our people. Reaching the quarter-finals brings joy, but the road now becomes very hard. We will have to compete as we always do. It will be difficult."

He added: "We are probably facing the team that attacks best in Europe, but we will go with our enthusiasm and our desire to compete."

One of the key figures on the night was Julian Alvarez, who delivered a decisive performance with a goal and an assist at the Tottenham Hotspur Stadium.

Simeone was full of praise for the forward, highlighting both his quality and intelligence.

"His match was incredible," Simeone said. "He showed vision, hard work, and he understood every detail of the game. He scored a great goal and gave us an attacking threat that meant we could always create chances."

Looking ahead to the quarter-final clash, Simeone left no doubt about the size of the task.

"We will try to compete with Barcelona," he said. "I have no doubt they are the best attacking team in Europe. A quarter-final against them is of the highest level, and it will demand everything from us."

FC Barcelona produced a stunning 7-2 win over Newcastle United on Wednesday to reach the Champions League quarter-finals with an 8-3 aggregate victory.

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