Madrid host Napoli in the Champions League on Wednesday with eight players absent through injury -- Thibaut Courtois, Kepa Arrizabalaga, Éder Militão, Eduardo Camavinga, Aurélien Tchouaméni, Luka Modric, Vinícius Júnior and Arda Güler -- and many pointing to the packed fixture list as a contributory factor.
"For a top player playing at a top club, the calendar is very demanding," Carvajal told a news conference on Tuesday. "With the new Club World Cup, we won't ever get a summer off. I agree with [coach Carlo Ancelotti] and other people who've said there are too many games. So many injuries isn't a coincidence.
"The players are the ones who play, and it's hard to reach an agreement between everyone. It's complicated. But what's a reality is there are lots of injuries, and I think a lot of them are due to the calendar."
Spain international Carvajal has himself suffered frequent injuries in recent years but has found career-best form this season, making 12 starts in LaLiga and three Champions League appearances.
"A lot of people say 'why don't [players] cut their salaries?'" Carvajal added. "We haven't said we wouldn't. If we had to earn less and play fewer games, it wouldn't be a problem. You don't see players at their best, and the games are dropping in quality, that's the reality."
Despite their injuries, Madrid are top of LaLiga and lead Champions League Group C with four wins out of four.
"This is Real Madrid, you don't score for three games [in a row] and you get criticism," Carvajal said. "I'm happy for him, that the pressure is off now. When he starts scoring, you can see the effect on the team. I hope it keeps going."
Star midfielder Jude Bellingham scored against Cadiz on Sunday to make it a record 14 goals in his first 15 games for the club, after recovering from a dislocated shoulder.
"I think Bellingham is really intelligent, professional, serious and mature," Ancelotti said. "But the most important part is he's a fantastic player, and a fantastic player can adapt anywhere, in any country."