The visitors effectively threw in the towel after a damaging draw with Levante but they can now retain their Primera Division crown by winning their final two games
Gerardo Martino's men know that they would retain their title if they win both of their remaining two matches after leaders Atletico Madrid and third-placed Real Madrid failed to take advantage of the Catalans' 2-2 home draw with Getafe.
Atleti lost 2-0 to Levante 24 hours after Barca's slip-up at Camp Nou, while Los Blancos only took a point from their match against Valencia and then drew 1-1 at Real Vallodolid in midweek.
Barca now sit three points adrift of Atleti and one ahead of Real, with the Blaugrana scheduled to host Diego Simeone's team on the final day of the season.
Elche, however, will likely provide stern opposition for the reigning champions on Sunday. Fran Escriba's side are unbeaten in their last nine home league matches and know that a point against Barca would assure their top-flight survival.
Martino's men are unlikely to have too much trouble stifling an Elche attack who have scored just 29 goals in La Liga this season but breaking down one of the meanest defence in the bottom half will be a challenge. The hosts have shipped just 47 goals this term, conceding only twice at the Estadio Manuel Martinez Valero since the turn of the year and Escriba is hopeful of providing yet another twist in the title race.
"We have to be more intense than in the game at Camp Nou. I trust that we will score and we can win," he told the press.
Barca ran out 4-0 winners in the reverse fixture, with Alexis Sanchez grabbing a hat-trick on that occasion.
Elche will be without goalkeeper Tono and defender Alberto Botia through suspension while Barca have longstanding injury worries throughout the squad with regular first-teamers Victor Valdes (knee), Carles Puyol (knee), Gerard Pique (groin), Jordi Alba (hamstring) and Neymar (foot) all unavailable.