The Spaniard moved to Old Trafford on Saturday and was officially unveiled as the club's new no.8 on Monday. His full debut against Cardiff City followed just a day later, capping a remarkable 72 hours for the 25-year-old.
Speaking after Tuesday's 2-0 win over Cardiff City, Mata tried to reflect on his short time at United so far and explained how everybody has welcomed him to the club.
"Time has gone so quickly since I arrived here," Juan told ManUtd.com and PA Sport. "I only trained twice with the team but the welcome was amazing. The lads are really good. There is a great atmosphere. I am very happy and looking forward to the next game.
"The stadium is unbelievable," Juan went on to say. "The fans are so loud, even before the game. It has been an amazing time for me. Even social media has shown me so much. The amount of fans this club has is unbelievable.
"I have felt comfortable at this club from the first minute. The players have made me feel like this. To be honest last week I didn't train that much because of the transfer. I can improve. But I felt okay. I felt good playing alongside these players."
Having recorded a fine 2-0 victory over Cardiff, Mata is keen to maintain that winning feeling and move closer to the Barclays Premier League summit.
"We need to sustain that feeling for sure. I am always positive. If any club can come back and climb the table it is this club. We will try to win as many games as we can to the end of the season, hopefully all of them."
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