In The Ignatius Study Bible: The Gospel of Matthew, by Scott Hahn and Curtis Mitch, pub. by Ignatius Press, in 2000, on Matthew 6:11 says:
The Greek word epiousios (translated daily) is used only here and in Luke 11:3 in the New Testament. It probably means “for tomorrow” or “for the future”. The petition thus concerns food for the body and soul: (1) The necessities of life that fathers gave their children is a form of daily bread. This may recall the manna that God provided each day for the Israelites in the wilderness (Exodus 16;13-17). (2) Several Church Fathers interpret daily bread as a reference to the Holy Eucharist–a form of supernatural sustenance (Acts 2:46). The two connotations are connected, since Jesus advocates dependence on the Father for daily living (Matthew 6:25-34) and later associates the manna with the Eucharist (John 6:30-40; Catechism of the Catholic Church, 2837)