As many as five Valencia players and staff are tested positive for coronavirus.
Their defender Ezequiel Garay became the first one to be contracted with the virus, followed by Eliaquim Mangala.
“Players and staff were in their homes in good health and under isolation measure,” the club told.
“We are confident that with solidarity, responsibility and good spirits we will beat this pandemic.”
Valencia’s Champions League opponent in Round of 16, Atalanta had already went into self-isolation since last week.
Spain is the second worst country in Europe to be affected by the virus after Italy declared a national lockdown.