Mata and Herrera reportedly feel stifled by van Gaal's tactics.
The report says that Ander Herrera and Juan Mata will look for a move if the Dutchman manages to survive beyond this season. But after recent poor form and poor football, it looks as if it will take some turnaround for van Gaal to hold on to his job at Old Trafford.
Mata was signed during the January transfer window of David Moyes' brief tenure at Old Trafford, while it was widely reported, including the Daily Mail, that Herrera was targeted by the Scot but he was only signed after being approved by van Gaal shortly after his appointment.
However, given that Jose Mourinho appears to be the front runner to succeed Van Gaal if the Dutchman is sacked, then it is hard to see that Mata will want to stick around anyway, given the way he was handled by the Portuguese prior to his move to Old Trafford.
He has, however, often been seen as one of the more integral parts of the United side under van Gaal having featured in every Premier League game this season, and he has scored five goals in all competitions.
Last season Mata managed to find the net on 10 occasions, although creativity has not really been the strong point of United under van Gaal this season.
Some have been baffled by the United boss and his handling of Herrera however, who seems to be one of the side's better central midfield players and a decent goal-scoring threat, but has not been used as much as people would like.
The report says that both players mentioned have felt stifled with the tactics undertaken by van Gaal.