 While there he probably taught Gian Matteo Asola and Marc' Antonio Ingegneri, the teacher of Monteverdi; it is possible, though not proven, that he taught Andrea Gabrieli there as well.His music during this time was strongly influenced by the Franco-Flemish school, but when he in 1563 became "maestro di cappella" in the cathedral of Milan under Carlo Borromeo, he began composing in the Tridentine style of which Borromeo was a strong supporter.One of the criticisms of the Council of Trent was that music had become so contrapuntally complex that it was impossible to understand the words being sung