Deuleofeu suffered an anterior cruciate ligament injury sustained against Liverpool last week.
He has since undergone surgery in Barcelona and issued the following statement via his Twitter account.
"I always thought that it wouldn't happen to me, that this fatal moment wouldn't arrive at all but, well, it happened to me indeed...
"But I can tell you that 10 minutes later, and with the love and help of my family at this very difficult time, I already knew and envision how to confront these next few months. I am ready to fight for this sport the I love so much!"