German midfielder acknowledged hopes of retaining the Primera Liga title are now over after Saturday's loss to Villarreal.
Toni Kroos: Qualifying for the Uefa Champions League is the goal now for Real Madrid
Real Madrid midfielder Toni Kroos said the Spanish champions cannot defend their title and are fighting to finish in the Primera Liga's top four after their defeat to Villarreal on Saturday.
Madrid are fourth in the table after their 1-0 home defeat, 16 points behind leaders Barcelona.
The gap could have increased to 19 points if the Catalans triumphed against Real Sociedad in last night's late game.
Zinedine Zidane's side have struggled this season and have won one game in their last five in all competitions, against third division Numancia in the Copa del Rey.
"We have to focus on qualifying for next season's Champions League," Kroos told BeIN Sports USA. "I think this should be our goal for the rest of the season.
"Sixteen points is very far behind and it's not the moment to think about anything that is not the next game and returning to winning points to bring us close to Real Madrid's objective, which is to finish in the top four."
The hosts created chances against Villarreal but were kept at bay by superb goalkeeping from Sergio Asenjo, before Pablo Fornals' perfectly-executed chip consigned Zidane's side to defeat.
Madrid have only managed to accumulate 32 points after 18 matches, which is their lowest points total at this stage of the season since the 2005-06 campaign when they had 30.
Fans made their displeasure at Madrid's recent performances known at the Santiago Bernabeu, jeering and whistling as their team trudged off the field.
"Those in the upper echelons of the Madrid hierarchy are now firmly on the fans' side, laying the blame at the dressing room door as this crisis period unfolds," wrote Spanish newspaper Marca, of the mounting pressure on coach Zidane.
The Frenchman has repeatedly stated he has signed a contract extension at Madrid until 2020, although the club has made no official announcement.
Zidane has also said the league title is out of Madrid's hands and should they fall to Paris Saint-Germain in the Uefa Champions League last 16, his position will be at risk.
"Inexplicable" was the front-page headline of Marca yesterday, which remarked that the reigning Spanish and European champions "don't know what is happening to them" in the league.
Just days after Zinedine Zidane signed a new contract until 2020, serious questions are being asked of the Frenchman's ability to turn things around after two trophy-laden years in charge.
Real have picked up just one point from their last three league games and have won only once in five, form that leaves them fourth in the table, 16 points behind leaders Barcelona, who go to Real Sociedad on Sunday.
"No goals, no luck and no explanation," said sports daily AS on their front page.
"Everything is going wrong," wrote editor Alfredo Relano in his column. "This result sinks Madrid further into the sombre mood that has invaded everyone, including Zidane."