Xavi believes Barcelona cannot afford to underestimate Real Madrid in the first leg of their Copa del Rey semi-final on Wednesday.
Real will have to make do without the likes of Iker Casillas and Pepe due to injury, but the Spain midfielder has stressed that Real are always difficult opponents no matter who takes the field.
"These games are always unpredictable. We are really in good shape to compete right now but anything can happen in football, and particularly against Real Madrid," Xavi told The Times of India.
"They will be missing a few important players, but they are Real Madrid after all and they will compete well, I'm sure. Despite their current situation, they are a dangerous opponent."
The Spain international is also wary of Barca's Champions League round-of-16 opponents AC Milan.
"Milan are a tough side. They've always made life very hard for us defensively. San Siro is not an easy place because the fans are very passionate," he said.
The first leg of that clash is scheduled takes place on February 20.