Mata played 83 minutes in last weekend's 4-1 victory as goals from Anthony Martial, Chris Smalling, Paul Pogba and Romelu Lukaku cancelled out an early Dwight Gayle strike for the Magpies.
Not only was Gayle's goal at Old Trafford the first time Jose Mourinho's men had conceded at home this season, it was also the first time his side had come from behind to win.
Mata assisted Lukaku for the final goal of the game, helping the Belgium international end his goal drout for United and expressed his delight at how his teammates responded from going a goal down.
Speaking in his Monday blog, Mata said: "Saturday’s victory was special because it was our first comeback win of the season. So far, in most of the games we had scored first and won.
"Against Newcastle, though, we conceded a goal and then we had to come back," the Spaniard said, "and the way we did it illustrated our ambition and character.
"Newcastle are always a tough opponent, a well-crafted team with good players, but we were able to defeat them with a complete performance from the whole team," he added.
Mata prepared for festive fixtures
United now face a crammed fixture list heading into the winter period, starting with FC Basel in the Champions League on Wednesday night - with Mata expected to make the trip to Switzerland.
The 29-year-old also added the importance of getting a positive result in Europe, despite the Reds being already through to the last-16 of the competition.
"First of all we travel to Switzerland to play Basel in the Champions League." Mata added. "They are second in the group and are currently level on points with CSKA Moscow, which shows the importance of this game for them, but also for us: we are Manchester United and we are committed to winning every single game."