Nico Williams is the latest Spain player on the treatment table as he described dealing with an injury after the 1-0 win over Uruguay as "one of the worst days of my life."
Williams, the 23-year-old Athletic Bilbao player, was fouled by Nicolas de la Cruz in the final group match on Friday and then was seen limping on his right leg.
On Saturday, he wrote on social media: "Today is one of the worst days of my life. After a very difficult year I have injured myself again."
He said his opponent had caused him an injury "out of frustration, dissatisfaction and sadness" that could have "been avoided because it was completely unnecessary. But even that will not stop me."
Williams insisted his tournament was not over and said, "See you as soon as possible at this World Cup." Spain initially did not issue a statement on his status.
Spain coach Luis de la Fuente meanwhile fears that forward Yéremy Pino could miss the rest of the World Cup with a shoulder injury.
Pino came on as a substitute during the second half in Guadalajara but got injured late in the game.
The player from Conference League winners Crystal Palace managed to complete the match but examinations are to determine the exact nature of the injury.
"Unfortunately it could be a collarbone injury," De la Fuente said post-match.
Fearing the worst because Pino was in big pain, he added: "He has an injury that could lead him to miss the [remainder of the] World Cup."
De La Fuente praised Pino for completing the match despite the injury as Spain had already made their five allowed substitutions.
"I am very grateful to him, and his team-mates are even more so," the coach said, naming Pino's attitude "heroic."
European champions Spain finished top of Group H.
