Barcelona have announced that Tito Vilanova's operation on his parotid gland had gone "as expected" as the 44-year-old began a second battle with cancer.
Vilanova, who also had a tumour removed from his throat in November last year, will now start six weeks of chemotherapy.
In a statement, the club said: "Vilanova's surgical procedure has gone as expected. His clinical progress will determine how long he remains in hospital. The expected timeframe has been maintained. Tito asks for his privacy and confidentiality to be respected."
The club's captain, Carles Puyol, was more positive, saying the operation had gone "very well".
"The first message I have received is that the operation has gone very well," Puyol told a news conference after surgeons operated on Vilanova on Thursday, just over a year after he underwent a similar operation on his salivary gland.
Captain Carles Puyol said the Barça players have drawn strength from Eric Abidal's return to good health as they come to terms with news of Vilanova's need for further cancer treatment.
"You're never prepared to hear news like this, but (Eric) Abidal's example gives the team strength and I'm sure Tito's case will do the same. It's not just an example to us but to the man in the street, proving that if you fight hard, everything will be fine.
"The best way to support him is to keep moving forward. It is a severe blow but we must get up and keep on playing. This team has always done that and will do so again."