Zinedine Zidane is not sure if Eden Hazard will play again for Real Madrid this season.
The former Chelsea playmaker is facing another lay-off after fracturing an ankle in Real's surprise defeat to Levante in LaLiga last weekend.
It was only the Belgian's second appearance since November after recovering from another injury to the same ankle.
The loss of the 29-year-old, who is yet to make his mark since his £89 million move from Stamford Bridge last summer, is a big blow to Zidane at the start of a crucial week.
Real host Manchester City on Wednesday in the first leg of their Champions League last-16 tie before facing arch-rivals Barcelona, who leapfrogged them to top spot in La Liga last weekend, on Sunday.
Speaking at a press conference, Zidane said: "He loves playing football and while I can't tell you what is in his eyes, I can see he is not happy.
"It's important he stays positive but, of course, it's difficult. It's a bad moment, it won't be easy and he will feel like that for a while.
"I do not know if he will have to go through an operation. It is not my area and I don't know if his season is over, but I hope not."
Zidane would not comment on suggestions Hazard's rehabilitation from his previous injury was not handled correctly.
"I am not the right person to say what should have been done or shouldn't have," said the Frenchman.
"They are professionals and very capable in their area.
"We are not happy about Hazard's injury, it comes at a bad moment. He wanted to play and help us but now he is out again, which is sad of course.
"I hope when he's back again he is completely fit. That's what everyone wants and that's it."
Raheem Sterling is fit and ready to face Real, according to Manchester City boss Pep Guardiola.
The England forward has been out since suffering a hamstring injury in the 2-0 defeat to Tottenham on February 2 but is in line to return at the Bernabeu for Wednesday night's last-16 first leg.
Guardiola said: "Raheem is fit. His physical condition and regeneration is amazing. He said he could have played against West Ham and Leicester but the doctor said it was too soon. But that was a good sign."
The meeting with Madrid is City's first Champions League game since they were handed a two-year ban from European football by UEFA for breaking Financial Fair Play regulations.
The Premier League champions are appealing against the sanction and Guardiola does not believe this season will be the last chance for the current side to win the Champions League.
"No way," he said. "These players will have many chances to win. We know the challenge...but it's not the last one."
On the ban, Guardiola added: "We were under suspicion for a long time but we have the right to appeal. I trust the people in the club. They showed me the arguments and we are optimistic. If it doesn't happen we have to accept it."
The Champions League tie brings Zidane, who has guided Real to three victories in the competition, up against Guardiola, a two-time winner with Barcelona.
Despite having one more success to his name, Zidane claims his opponent is the better coach.
He said: "He has shown that over the years, at Barca, Bayern and now City. That's my opinion. Some people can think other coaches are better but for me, he is the best.
"But it is Madrid against City, not Zidane against Guardiola. It will be a great game. We always want to play games like this and we will do our best to come away with a good result."
City go into the game with a cloud hanging over them after they were banned from the competition for the next two years by European governing body UEFA over Financial Fair Play breaches.
Real captain Sergio Ramos, however, believes that could motivate City.
"It's hard to know. Fortunately it's not something that happened to us," he said.
"Obviously it's bad news for the players that want to keep playing in the competition but also it's a good way for them to have motivation and to want to show what they're capable of.
"And when they return in three years perhaps they will want to win more than ever."