Spanish newspaper Marca, as quoted by the Daily Mirror, is reporting Mourinho is prepared to allow Herrera and Mata to leave the Red Devils at the end of the 2017-18 season.
The same article is keen to stress that the Portuguese head coach isn’t actively looking to sell the Spanish pair but isn’t opposed to their departures.
Mata, of course, extended his current deal with Manchester United for another season and won’t be a free agent until the conclusion of the 2018-19 campaign.
The former Chelsea FC midfielder has scored four goals and has made five assists in 39 games in all competitions this term.
Herrera has found his first-team opportunities limited following the arrival of Serbia international Nemanja Matic in a £40m deal from Chelsea FC last summer.
Manchester United are in second place in the Premier League table and two points ahead of Liverpool FC in the race to secure a spot in the Champions League.
The Red Devils will take on Tottenham Hotspur in the FA Cup semi-final at Wembley next month.
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