He spent four years working alongside Guardiola as his assistant at Barcelona in an era which saw the Catalan giants dominate the continental game by claiming two Champions League titles and eight domestic trophies.
Speaking to reporters following his side's 5-2 win over Werder Bremen on Saturday, the Spaniard described Vilanova as "more than a friend" and claimed that he will never fully get over his passing.
"It was difficult for me to follow the match today," he said. "Tito was more than a friend. The sadness I feel will accompany me for the rest of my life. We were young, we wanted to beat the world, and we did."
Barcelona have announced that the funeral will take place on Monday.