Real Madrid midfielder Casemiro admits they fell well short of standards in their thrashing at PSG.
Real slumped to a 3-0 Champions League defeat against Paris Saint-Germain.
"The truth is that we didn't play well," Casemiro told Movistar. "They took control of the game and we know that it's always very difficult here.
"They're very strong, they have great players and there is no excuse.
"We're going to keep working... there's still lots of time to change this.
"We always try to be aggressive, but when the result is 3-0 we know that things are noted more.
"We know that if you don't play a pretty much perfect match here, you don't win.
"There's lots of time to change this."
Los Blancos posed very little attacking threat and weren't able to find a way past Keylor Navas in the PSG goal.
"We had chances," Casemiro said. "We scored two goals that didn't stand, but I don't think there's an excuse right now.
"We didn't play well. It's a delicate moment to speak, but we're working and we have time to change this."