The Spaniard is approaching his 250th appearance for The Red Devils after arriving from Chelsea in 2014, scoring 48 goals and providing 42 assists in 249 games.
Speaking in a video on United's Twitter account, Mata said: "It feels like it has gone very quickly, it feels like time flies. I didn't know it was going to be my 250th game, but I feel proud.
"When you play your first game you feel like you are in a new beginning, a very exciting moment in your life playing for this club.
"I don't want to stop here, I want to keep going and going, and keep adding games in a United shirt."