The Spaniard has struggled to make an impact at Old Trafford since moving from Chelsea for a club record fee of £37.1m in January.
Silva, who will face his international colleague in the Manchester derby on Tuesday evening, believes that United have not made the most of Mata's talents.
"They have not managed to bring out the best out in him but he is a very talented player and he will show it," Silva told The Independent.
"He wasn't getting the minutes at Chelsea so it was a good move for him to go to United."
Mata featured as United secured a 2-0 win over West Ham United at Upton Park on Saturday.