Man United will be looking to bounce back from their 1-0 defeat at Chelsea before the international break when they welcome Newcastle to Old Trafford.
Mata has said that his team need to be wary of "big club" Newcastle, and the Spaniard also paid tribute to Benitez, under whom he worked at Chelsea.
"We return to training with the mindset on the Newcastle match and the importance of the months that lie ahead, as they come loaded with games, especially during the Christmas period," Mata wrote in his weekly blog.
"These are moments in which good form of the team can be decisive for the second part of the season. Returning now to our game against Newcastle on Saturday, everyone knows they are newly-promoted but they are still a big club with several Spanish players.
"Among them Rafa Benitez, a manager with whom I was lucky to work with in the past. It will be nice to see him again. We hope to play a good game that allows us to get all three points, and continue showing that strength in Old Trafford."
The Red Devils are currently second in the Premier League table - eight points off the leaders Manchester City.