While Barcelona knocked out reigning Italian champions Napoli on Tuesday, a gritty Atletico side fought back from 2-0 down on aggregate to eliminate runaway Serie A leaders Inter Milan in a penalty shootout the next day.
As the season enters the home stretch, progress to the last eight in Europe's elite club competition was of paramount importance to Atleti boss Diego Simeone, who has seen his side fall behind in LaLiga's title race in recent weeks.
They were also knocked out of the Copa del Rey semi-finals by Athletic Bilbao and lost 2-0 at relegation-threatened Cadiz last weekend and sit in fourth on 55 points, 14 behind leaders Real Madrid, but Simeone is hopeful they have turned a corner.
"We came from a bad game in Bilbao in the semi-final, an ugly match in Cadiz... Honestly, I was trying to convey that it was not the time to ask but to give. I had to tell the players, 'Let's give it all'," Simeone said.
"The game in Cadiz ended and it looked like we had no chance against Inter. I said: '... it's the best thing that can happen to us'. It's when the team can have a reaction.
"And it happened. They gave their all, they played a great game, we have great players."
Barca won the reverse fixture 1-0 at home where Joao Felix, on loan from Atletico, scored the winner - a goal that stung the Madrid side who spent a club record 126 million euros ($137.73 million) to sign him in 2019.
UNBEATEN RUN
Simeone's side have it all to do against Barcelona who are on a seven-match unbeaten run in the league.
Barca sit third with 61 points, six ahead of Atletico, but coach Xavi, who is stepping down at the end of the season, said they have improved from last year when they won the title.
"We are playing better than last year, despite the results. We are under construction, Barcelona will continue to be under construction," Xavi said.
Real Madrid (69 points) will have the opportunity to extend their seven-point lead over Girona when they travel to Osasuna on the back of a 22-match unbeaten streak just over two hours before the second-placed side visit Getafe.
Real, whose progress to the Champions League quarter-finals last week after scraping through against Leipzig mean there are three Spanish teams in the last eight, have not lost to Osasuna in 20 games in all competitions.
However, Real's England midfielder Jude Bellingham remains suspended following his red card for remarks to the referee after their draw with Valencia.
Girona have also fallen by the wayside after leading the league, losing three of their last five games, but are still well on course for a spot in next season's Champions League.
They visit mid-table Getafe who have not kept a clean sheet in seven games and suffered a hammer blow with Borja Mayoral, LaLiga's second-top scorer this season with 15 goals, set to be sidelined for the rest of the season with a knee injury.
