The Red Devils have started to falter in the Premier League in recent weeks after dropping points against Swansea City and West Ham United over the past five games.
Louis van Gaal’s side are in fourth place and two points ahead of nearest rivals Liverpool ahead of the visit of top-four chasing Tottenham Hotspur at Old Trafford on Sunday.
Speaking during a question and answer session on Facebook, Mata underlined the importance of United finishing in the Champions League qualifying spots this season.
Mata wrote: “This [top-four] is obviously our main objective until the end. Manchester United must always play in the Champions League, and we believe we´ll make it!”
Mata hasn’t started a game for the 20-time English champions since a 3-0 victory over Cambridge United in their FA Cup fourth-round replay on 3 February.
The 26-year-old, who moved to Old Trafford in a £37.1m deal from Chelsea in 2014, has scored five goals and has made three assists in 23 Premier League appearances under manager Van Gaal this season.
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