Last week, the LFP announced that the club would not be able to take part in the Segunda Division, due to their off-field troubles.
And on Thursday, the league confirmed that Murcia would be demoted to Segunda B, the third level of Spanish football.
It is a sudden fall from grace for Murcia, who finished fourth in the second division last season, before being beaten in the promotion semi-finals by Cordoba.
A statement released by the LFP confirmed the sanction, while Murcia's place looks set to be taken by Mirandes, who finished the highest of the sides in the relegation zone at the conclusion of last term.
League president Javier Tebas spoke at a press conference following the announcement, and confirmed that the vacant position left by Murcia had been offered to Mirandes.
"First the documentation work must be completed, but we have no doubt that they will not have any problems with that," he said.
"During the season, the clubs are assessed financially and Mirandes have shown no signs of financial risk.
"They [Murcia] have not been registered because they did not meet the economic ratio requirements set out during the LFP Assembly for this season.
"If there is a judicial or administrative body that requires us to change our decision we will do so.
"Real Murcia have the right, and the duty, to defend their interests wherever they see fit."
