The 31-year-old moved to Old Trafford from Chelsea in 2014, becoming a popular figure within the dressing room and the support base.
Mata’s current deal at United expires at the end of June but Press Association Sport understands negotiations over a new deal have gone positively.
The attack-minded midfielder has scored 45 goals in 218 appearances for United and a new contract will be a boost for a club in the midst of change.
Combative midfielder Ander Herrera and captain Antonio Valencia are leaving on free transfers, while there are questions marks over a number of other key players.
Paul Pogba is keen for a “new challenge” and Romelu Lukaku would welcome an Old Trafford exit, while question marks remain over the future of Alexis Sanchez and David De Gea.
Swansea’s Daniel James is the only summer arrival so far, while United are interested in Aaron Wan-Bissaka and Harry Maguire.
