Barcelona vow to stand by Tito Vilanova as he battles cancer for second time
Adidas AbsoladoVilanova had an operation to remove a tumour in his saliva glands 13 months ago but is undergoing further surgery on Thursday after suffering a relapse.
The 44-year-old Spaniard will then have six weeks of chemotherapy, with no date set for his return.
Rosell said: "Tito is strong, very strong. He's shown us that and we're convinced he'll back with us very soon.
The Spanish press have already linked Pep Guardiola, who left Barcelona in the summer, with a return to the Nou Camp, but sporting director Andoni Zubizarreta denied any contact had been made.
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