From now on the Spaniards began to collect information assiduously about China, from not only the Portuguese and Philippine merchants in the islands, but also from Chinese immigrants and traders ("sangleys") in Manila and elsewhere.

At the same time Legazpi, now approaching 70, was proving himself to be a conquistador second to none. He wrote again to the king that "with God's help we could easily, and with not too many people, subject them". In February 1572, after some delay, Viceroy Enríquez in New Spain, who remained the supreme authority for the Philippines, gave instructions of a new kind to Juan de la Isla, earlier one of Legazpi's captains, to carry on a little further, the discovery of China. He was to be given three good ships. King Philip in Spain, no doubt exhilarated by the news of the recent great victory of the Spaniards and their allies at Lepanto, seems to have personally approved. The instructions of Enríquez to de la Isla not only approve a journey of exploration but "the seizure of Spanish land". 

Thus it was that the "China project" (la empresa de China) established itself in the minds of the Viceroy, the Council of the Indies in Castile and the governor of the Philippines in Manila.

In those days the ambitions of the Spanish conquistadors seemed limitless as can be seen from a letter sent home to Castile in January 1574 by Hernando Riquel, the chief notary of Manila. That official actually thought China could be conquered by fewer than 60 good Spaniards. In July of that year Guido de Lavezaris, the new governor of the Philippines (Legazpi had died), told the Council of the Indies that he certainly hoped for Spanish expansion into those lands: "I trust that there may be support for this work worthy of gods to enlarge and increase Your Majesty's dominions, and, at the same time, to carry true knowledge of the Catholic faith to so many who are barbarous and blind..."

The prospect of a Spanish invasion of China began to preoccupy Viceroy Enríquez — that was natural since it was up to him to choose the right person to lead a Spanish expedition to the country of the Ming. In the end he named Juan Pablo de Carrión, another of Legazpi's earlier lieutenants, and with experience in the Moluccas. Carrión was completely convinced of the benefits of conquest: "Those islands [that was China] are so well provided for and so rich and so large in comparison with the Philippines, that it would be worthwhile doing almost anything to reduce them to Spanish control." He offered to build and fit out at his own cost two galleons and two pinnaces to undertake the conquest.