Espanyol coach Mauricio Pochettino says the club are still in shock following the death of captain Daniel Jarque on Saturday.
The 26-year-old Jarque suffered a heart attack during the club's pre-season tour of Italy, and died in his hotel room as club doctors fought to revive him.
Over 50,000 fans visited the club's new El Prat-Cornella stadium on Sunday to leave their tributes.
"He was an outstanding person and a great professional,'' Pochettino said in comments reported by AS. "This is a great loss for his family and for Espanyol. It is very hard to take.''
Pochettino was speaking after he and his players visited the tributes that have been made to Jarque outside Gate 21 - Jarque's squad number - of the club's new stadium, which many fans now want to see named in his honour.
"We do not yet believe what has happened,'' the coach added. "It has been a huge blow, and it is very sad. We are all full of pain, something inexplicable has happened.''
Jarque's body is to be returned to Spain on Monday after a post-mortem was carried out, and his funeral is expected to take place on Wednesday.