Real Madrid right back Dani Carvajal picked up a hamstring injury in training, the club said on Thursday as their defensive issues continued to pile up ahead of next week's Champions League semi-final, second leg against Chelsea.
Local media reported that the defender could miss the European fixture next Wednesday as well as the La Liga title run-in as Real attempt to defend their league crown.
Real, who sit two points behind league leaders Atletico on 71 points and face Osasuna on Saturday, have not put a timescale on Carvajal's return.
"Following the tests carried out today on our player Dani Carvajal by the Real Madrid medical department, he has been diagnosed with an injury to the semimembranosus muscle in his right leg," a statement read.
Carvajal's season has been blighted by injury and he has made just 15 appearances in all competitions.
Lucas Vazquez, who filled in at right back during Carvajal's absence, has been ruled out for the rest of the season with a knee injury, while captain Sergio Ramos has a calf problem and has missed the club's last nine games.
Left back Ferland Mendy missed the first leg against Chelsea, which finished 1-1, with a calf problem.
Marcelo, who filled in for the Frenchman on Tuesday, could also be absent next week after Spanish media reported he had been called up to work at a polling station in the Madrid regional elections.
Meanwhile, Thomas Tuchel has told Timo Werner to "put his chin up" and forget his major missed chances against Real Madrid.
Christian Pulisic's calmly-taken goal cemented Chelsea's early dominance in Madrid, but Karim Benzema fired his 71st Champions League goal with an unrivalled piece of finishing.
Germany forward Werner had two gilt-edged chances to put the Premier League side firmly in the driving seat, but the Blues will still take an away goal into the second leg at Stamford Bridge on Wednesday, May 5.
Chelsea boss Tuchel admitted the misses caused consternation on the night, but called on Werner and the rest of the Blues to shake off that feeling without delay.
"He missed a big one in West Ham, now he missed another big one here," said Tuchel, of Werner.
"That does not help, but it also does not help to cry about it or to regret it all the time; it is like this.
"There are millions of people who have harder things to deal with than chances that you miss, so this is the good thing about sports – nobody cares tomorrow.
"We were sad, we were angry in the moment, this is normal. He was angry. He may be disappointed. Now he has a free day and the next day he has to put his chin up.
"He is a professional guy a top guy, he works hard. He is in positions and from there on we go.
"We will never stop pushing, we will never stop believing and I have the feeling that everybody accepts the situation like it is and as a striker it is easy, you score the next game and nobody speaks about it."
