Louis van Gaal’s men have struggled to find consistent form in recent weeks but left Merseyside with all three points thanks to Wayne Rooney’s 78th minute winner.
The result lifted United up to fifth place in the Premier League table and two points behind fourth-placed Tottenham as the Red Devils look to close in on qualification for next season’s Champions League.
Mata was thrilled with his side’s overall performance after the 27-year-old played the final 24 minutes against Jurgen Klopp’s side at Anfield.
United are now gearing up for their Premier League clash against Southampton at Old Trafford this weekend, and Mata has warned that the Red Devils can ill afford to underestimate their next opponents.
Mata wrote on his blog for Kicca: “I hope this win will give us a boost of confidence, and help us play better and keep getting results in order to move up the table. There’s a long way to go and there is no team who is showing a great consistency, so everything is still open…
“For the moment, we have to stay focused and keep the same mentality in our next game in Old Trafford against Southampton, the team of my friend Oriol Romeu.
“They have got two convincing wins in the last two games so we must be careful.”
Mata has scored four Premier League goals this season.
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