Mata is Cup-tied from the competition for United.
He wrote in his blog: "After last weekend's win against Crystal Palace, we could not win in the Champions League, suffering a painful loss in Greece. Moreover, as I can't play in the Champions League I had to watch the match at home and suffered as I couldn't help! Nevertheless, although it'll be difficult, I think we can comeback at Old Trafford with an incredible atmosphere thanks to our fans.
"A thrilling month is starting with five Premier League games against important rivals such as Liverpool and Manchester City. We do know it is a crucial month to climb up positions on the league table and we are going to give our best to try and win every single match."
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