Both players are in fine form, with Mata having scored twice in the 2-1 win at Liverpool, while Herrera mirrored his team-mate's effort in Saturday's 3-1 triumph over Aston Villa.
With the two having assisted one another for a goal apiece in those matches, Mata explained that the duo were on the same wavelength after becoming friends off the field during their days in Spain's youth teams.
"I think it's because of the relationship we've had over the years and because we understand football and life in more or less the same way," the former Chelsea man told the club's official website.
"I think we play well together because we understand each other and sometimes without speaking or looking we know where we're going to pass or where we're going to move on the pitch.
"The first goal at Anfield is a good example of that - he controlled the ball, turned and knew where I was already running to and he put the ball there. Ander is a quality player and I'm very happy he's here and playing and performing well."
The pair will hope to link up again in Sunday's derby against Manchester City, when United look to take another step towards a UEFA Champions League return.
