Mata's calm finish in the sixth minute put the visitors in control on Friday night, and they doubled their lead midway through the first half as Xabi Alonso slotted home a fine cut-back from Silva.
Del Bosque said on the Spanish federation's website, rfef.es: "We started very strongly and at the end we let go, but we had controlled the match.
"Our midfielders were able to dominate the entire game.
"Silva and Mata are very important players. They link up well in midfield. They had a great game."