The father of former Real Madrid coach Julen Lopetegui has said the club had "stolen 50 goals from my son" after failing to find a quality replacement for Cristiano Ronaldo.
Ronaldo won 16 trophies and scored 450 goals in nine seasons at Madrid before being sold to Juventus for €100 million in July following the Portugal captain's request to be transferred.
Madrid have struggled without Ronaldo and Sunday's 5-1 defeat at Barcelona saw Los Blancos drop to ninth in La Liga, which ultimately saw the club and Lopetegui part ways on Monday.
"Cristiano Ronaldo was good," Jose Antonio told El Mundo before Sunday's Clasico. "Was he cocky? We all have defects.
"But it turns out he [Ronaldo] scored 50 goals [a season]. He is missing. You are missing a prominent goalscorer. They haven't brought one, not a single one.
"There was talk of Neymar and others but no one came. They have stolen 50 goals from my son."
Madrid's only attacking additions were Mariano Diaz, who they re-signed after a season with Lyon and Brazilian teenager Vinicius Jr, who has made only two substitute league appearances and has played mostly for their reserves.
"Yes. He has to settle with what he has," Lopetegui Sr. said after being asked if Madrid had left his son exposed. "Don't get me wrong, he is delighted with the players he has.
"He usually says: 'I have great people, they give everything they've got.' He doesn't blame the players. But when there is no material, there isn't. There was but he [Ronaldo] left."
Lopetegui was supposed to coach Spain at the World Cup this summer but was dismissed after it emerged he had agreed to take charge of Madrid.
"The lads are delighted with him and listen," his father said. "Julen is not lacking money."
Madrid have taken one point from a possible 15 in their last five league games and the team has endured their worst start to a season since 2002.