Fernando Hierro will lead Spain at the World Cup after head coach Julen Lopetegui was dramatically sacked on the eve of the tournament.
Spanish preparations were thrown into turmoil as Lopetegui lost his job following Tuesday's announcement he would leave to take over at Real Madrid after the finals in Russia.
Spanish Football Federation president Luis Rubiales removed Lopetegui from the post just two days before the national team's Group B opener against Portugal.
Rubiales had been riled by being told of Lopetegui's decision to take the Real job just five minutes before it was made public.
Former Spain and Real Madrid captain Hierro, who moves from his role as the team's director of football, was set to be presented to the press at the Krasnodar Stadium later on Wednesday before getting to work in his new post.
Hierro also had a spell with Bolton in the Premier League at the end of his playing career.
"Fernando Hierro will assume the position of national coach during the World Cup in Russia and will appear before the media accompanied by the president of the RFEF, Luis Rubiales," said a short statement on the federation's website.
"Next, he will direct his first training and on Friday he will debut in Sochi at the match of Spain against Portugal."
Earlier in the day, Spain delayed a press conference at the same venue by well over an hour before Rubiales announced he had dismissed Lopetegui - pointing the finger of blame at Real Madrid, rather than the outgoing coach.
"We have been forced to dispense with the national coach. We wish him the best of luck," he said.
"I don't want to get into how Real Madrid should go about things. The Spanish team is the team of all Spain.
"If it had been up to Julen it wouldn't have happened in this way and I wouldn't have found out five minutes beforehand.
"The negotiation occurred without the RFEF having any information. (We were told) just five minutes before the press release. We have a way of behaving that needs to be adhered to.
"Obviously there was some sort of problem with communication but we can't be expected to find out about something like this five minutes (before the announcement) and not take the necessary decisions."
Sam Allardyce, who managed Hierro during his time at Bolton, thinks his former player could be well suited to the role as national team boss.
Allardyce told Sky Sports News: "As a person, as a man, he was a top, top guy. Around the dressing room and on the field he commanded so much respect, not just for his talent as a footballer but his human-being skills and what a person he was.
"I don't think he'll have any problem integrating into the team as their coach. His passion for football is unquestionable and he'll hopefully pass that over to his players and it won't be too big a loss losing their coach to Real Madrid."