Ousmane Dembele replaced Messi in the 25th minute after the Argentine was examined by club doctors on the sidelines following a challenge by Sevilla’s Franco Vazquez
The news has come as the stuttering Spanish La Liga champions prepare for a gruelling set of fixtures.
“Our player Isco has been discharged from hospital.
Everton forward Sandro Ramirez has joined Spanish side Real Sociedad on a season-long loan, the Premier League club have said.
Franco Vazquez put Sevilla ahead at Rayo in the 15th minute after each side had goals correctly ruled out for offside without using VAR
Sevilla made the breakthrough in the ninth minute of the match, although it would have been disallowed but for the invention of VAR, which showed that the linesman was wrong to flag Sarabia offside
The Spanish Football Federation has settled on the single-game format for Sunday’s encounter between Liga champions and Copa del Rey holders, Barca and cup runners-up, Sevilla.
A victory would also virtually assure them of a second domestic double in three seasons, reinforcing their dominance in Spain.