Zinedine Zidane defended Real Madrid's backroom team and said a congested fixture list was the main factor behind a lengthy injury list that now includes full-back Ferland Mendy.
Madrid confirmed on Tuesday that Mendy, who joined from Lyon for €48 million (£42m/$52m) in June, has suffered an abductor injury in his left leg.
The France international completed 90 minutes in the 1-0 win over Sevilla on Sunday but is now set for another spell on the sidelines, having previously suffered a hamstring injury shortly after he joined Los Blancos.
Zidane is already without fellow left-back Marcelo, as well as Luka Modric, Marco Asensio and Isco, but denied the slew of injuries was anything to do with his medical staff.
"I'm not worried but it does bother me that we have a lot of injuries," the Madrid coach said at a news conference.
"I don't want to see my players injured but that is part of football, we can't control it. You can take great care of the players, the backroom staff are very good. But not just that, you need sometimes a bit of luck.
"[Mendy] is an important player for us but things happen. In the games you have lots of demands. Really, nowadays players aren't resting.
"We have seven games in 21 days, they've all played for their international sides and they're going to have more international games after these games. It makes things difficult.
"Everyone can have an opinion and say, '[the backroom staff] are doing this wrong' but we need a bit of respect for these people – they have proven that they know their jobs.
"We work hard in pre-season, it's necessary to do that. There's lots of reasons why people can get injured in games and you have to accept it. It's not just Real Madrid that have injuries, all clubs do."
Zidane's side, who lost 3-0 to Paris Saint-Germain in the Champions League last week before returning to winning ways against Sevilla, face Osasuna on Wednesday prior to meeting Atletico Madrid in the derby on Saturday.
They then have home fixtures against Club Brugge and Granada before the next international break in early October.
"Current players nowadays are playing every three days," Zidane said.
"They went off with their international sides, they go off afterwards, there's no rest. When I played, we played 45 [games], now they're playing 60. It's almost two seasons in one at the moment. Perhaps this is the problem.
"Football changes and we're playing 60, 65 games and that gives you problems. I think it's complicated when you have players that go off to international sides.
"It's difficult sometimes when you lose and you give players a day off and you get criticised as well. There's a planning behind all of this. It's all planned.
"There's a lot of travelling, minutes on the pitch, so there will be injuries. Players aren't machines, they're human beings."
Zidane added that Marcelo, Modric and Isco were "about ready to come into the squad" following their lay-offs.