Sevilla winger Jesus Navas has been ruled out for three to four weeks after twisting his right ankle.
The Spain international sustained the knock during the first half of Saturday's 2-0 defeat to Espanyol.
Fellow playmaker Diego Capel picked up a problem in the same game and he is likely to be sidelined for 10 to 12 days with a muscle complaint.
Sevilla have also revealed that defender Sergio Sanchez is to undergo heart surgery in Germany in a bid to save his professional career.
The 23-year-old was ordered to stop playing by medics in January after being diagnosed with a heart condition.
"The doctor has explained the risks involved with this type of operation, because it is a complicated procedure, but he made it clear they are little when compared with the possible benefits," Sanchez told the club's official website.
"There is a good chance that I could continue my professional career if everything goes as we hope."
Meanwhile, Sevilla president Jose Maria del Nido has given coach Manolo Jimenez a vote of confidence in the wake of disappointing results.
The weekend setback at Espanyol allowed Real Mallorca to climb above them into fourth place in the table, with a four-match winless run putting a serious dent in their hopes of securing UEFA Champions League qualification.
"Anyone that has been in football for a long time knows that the fans demonstrate," said Del Nido after watching supporters express their disgust at recent displays.
"But the directors have to have the sense to not discuss this, not because this is the easiest thing to do but because it is in the best interests of the club."
He added: "The excuses about key players not being available no longer stands. Almost the entire squad is now available to the coaches.
"There are around two months of the season remaining and we have to be ready and we will see and try to work towards everyone continuing along the same lines to be successful again."