Sky Sports News is reporting that discussions are ongoing about the pair’s futures, with both of their contracts set to expire at the end of the current season.
Mata and Herrera are joined by Manchester United team-mates Anthony Martial, David de Gea and Ashley Young in being in the final year of their contracts at Old Trafford.
Their situation means that they could leave Old Trafford on free transfers in the summer if they do not sign new deals with the Red Devils.
Both Mata and Herrera have found their playing time to be somewhat limited at Old Trafford this season.
Mata has only started five of Manchester United’s 12 games in the Premier League, scoring one goal and making one assist in the top flight.
Herrera, meanwhile, has been limited to just two starts in the top flight – and he played 73 minutes of Manchester United’s 3-1 derby loss to Manchester City on Sunday.
Manchester United will be hoping to bounce back to winning ways after the international break when they take on Crystal Palace at Old Trafford on Saturday 24 November.
The Red Devils are currently eighth and 12 points off top spot.
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