Barcelona could look to replace Rafinha during the January transfer window.
Rafinha will undergo surgery next week for his injured ACL.
"It's something we have to analyse," Valverde said when asked if the club would look to sign a replacement for Rafinha in January. "The injury came as a surprise, because of how it happened. He was able to finish the game against Atletico, then on Sunday [we find out the extent of the problem].
"We will have to look at everything. The January transfer window is close, so we will have to look at the circumstances and see what we do."
Sources have confirmed to ESPN FC that Paris Saint-Germain's Adrien Rabiot and Ajax's Frenkie de Jong are both being considered, while Manchester United's Paul Pogba has split opinion at the club.