Kevin Gameiro's second-half penalty earned a laboured 1-0 win for Atletico Madrid at Deportivo Alaves, putting the onus on Barcelona to achieve a positive result in their clash with Deportivo La Coruna and wrap up LaLiga's title race.
Runaway leaders Barca only need a point in their fixture later on Sunday to be crowned champions regardless of the outcome at the Mendizorroza, according to Goal.com.
But Diego Simeone's men at least maintained their slim hopes, with Gameiro netting from the spot after Fernando Torres had already fluffed his lines from 12 yards out, Mubarak Wakaso having conceded both penalties.
The disjointed performance from Atleti was perhaps to be expected, Simeone leaving out the likes of Antoine Griezmann, Jan Oblak and Saul Niguez as he prioritised Thursday's Europa League semi-final second leg with Arsenal, a tie which is locked at 1-1.
Real Madrid can also mathematically still catch Barca, but it would require a remarkable sequence of events to deny Ernesto Valverde's side the title.
It could have been a different outcome on the day had Lucas Hernandez been judged to have fouled Munir El Haddadi in the area, but Diego Costa also failed to score a good first-half chance for Atleti before Torres' missed penalty after the break, the away team finishing with 10 men after Angel Correa received a second yellow card in injury time.