The Spain international was sent off inside 26 minutes of United’s 1-0 defeat by West Bromwich Albion at The Hawthorns on Sunday afternoon.
Mata will be suspended for United’s FA Cup quarter-final clash against West Ham United at Old Trafford next weekend.
However, the World Cup winner is desperate to put things right when Van Gaal’s side travel to Liverpool in the first leg of their Europa League last-16 clash on Thursday night.
“I must carry on as always and from now on I’m already focused on the next game, the derby against Liverpool in the Europa League,” Mata wrote on his blog.
“In this sport there’s no time for celebrations or moaning, and after last Wednesday’s joy for the win and the goal against Watford, now I have to go through a more bitter experience. That’s the way it is.
“What matters is to move forward and to always learn from each situation. And so I will.”
The Baggies scored their winner in the second half thanks to Salomon Rondon to inflict a first defeat in four games upon the Red Devils.
United are in sixth place in the Premier League table and six points behind fourth-placed Manchester City, who occupy the final Champions League qualifying spot.
United have won four of their last five games in all competitions.
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