Real Madrid also bagged a French international star as Eduardo Camavinga arrived from Rennes -- but their attempts to sign Kylian Mbappe from Paris Saint-Germain failed
This year is only the second in 17 that neither Barcelona nor Real Madrid have won the title, the other when Atletico last clinched the league in 2014.
Diego Simeone's side travel to relegation-threatened Valladolid knowing that if they better Real Madrid's result against Villarreal, they will be crowned champions.
"It's a final against Valladolid, with two sides fighting for their own different, but important, objectives and we will both give absolutely everything they've got to achieve it," Simeone told a news conference.
The Catalans practically surrendered their chances of catching La Liga leaders Atletico Madrid after drawing 3-3 at Levante on Tuesday and trail them by four points with two games left.
"It's not fair that one day everything seemed perfect and two weeks later everything is horrible."
But VAR prompted referee Juan Martinez to check an Eder Militao handball a few seconds before, with a huge decision seeing Madrid's penalty cancelled and a spot-kick awarded to Sevilla instead.
Simeone, however, insisted he would not change his usual set-up for a more attacking one.
"Sometimes it's gone really well and sometimes it hasn't. We don't change a lot. We'll try and play using the good points of how we've been playing up to now.
"The project is on stand-by. The project exists, but half of them have left, tired of what they have heard over 24 hours, saying they don't want to continue," said Perez.
The club, who were named as one of the 12 Founding Clubs on Sunday, confirmed this on Monday citing the COVID-19 pandemic for speeding up the instability in the existing European football economic model, while also saying they wish to improve quality of competition throughout the continent.
For weeks it has looked like only Real Madrid and Barcelona could overhaul struggling Atletico but 13 points from 15 has put Sevilla back in sight of the top three.
Asensio finally gave Madrid the lead late in the 41st minute after his side had two goals ruled out for offside, latching on to a Casemiro through ball and curling his effort into the bottom corner despite losing his footing as he took the shot.
Real then had a goal ruled out for offside for the third time but eventually got the all-important second goal when Benzema headed home a cross from Vinicius Jr. in the 73rd minute.
The Uruguayan's form has matched his team's, with a slight downturn in recent weeks perhaps inevitable after such an impressive first half of the season.