The Spanish playmaker has wished Anderson well on his return to Brazil.
The club have yet to officially announce the departure of the 26-year-old, but reports in The Daily Mail claim that Anderson is set to sign for Brasileiro Serie A side Internacional at some stage today.
Mata, who joined United from Chelsea last January, sent the Brazilian well wishes in his weekly blog post, writing: "Also, I want to wish good luck to my friend Anderson, who is back to football in his native Brazil. All the best, my friend!"
You can be sure that Mata won't be the only man at Old Trafford wishing Anderson well for his future. The former Porto player was quite a charismatic figure in and around the club and was known to be popular with his fellow colleagues.
United aren't likely to get back any percentage of the reported £20 million they parted with to bring Anderson in seven-and-a-half years ago. His contract is due to expire and the end of the season and you would have to imagine that the club will be more than happy to just have his wages off the books.
It will be a shame that when Anderson's departure is set in stone he will be dubbed as one of United's worst ever signings. When he joined in the summer of 2007, he came with so much promise and potential that he had adopted the title of the 'next-Ronaldinho'.
Injuries and fitness problems plagued his seven-year stay in Manchester though, and he only managed to score five goals in 105 Premier League appearances with just one of those coming in the previous season-and-a-half.
Despite both Anderson and Mata being at the same club for over a year now, they have only spent a grand total of 17 minutes on the pitch together and that came in the 0-0 draw at Burnley earlier this season.