The Spaniard joined United for £37.1m on Saturday.
After struggling this season Manchester United lifted their spirits on Saturday by securing Juan Mata from Chelsea in a £37.1m transfer.
The 25-year-old had been left frustrated at Stamford Bridge under Jose Mourinho due to a lack of game time and David Moyes saw the perfect opportunity to shore up the Reds Devils midfield.
Mata made his debut for the Premier League champions in the 2-0 victory over Cardiff City on Tuesday and team-mate Phil Jones says the arrival of the Spaniard has made all the United players perform better.
“It makes an impact in the dressing room when you sign a player of that calibre,” the England international told the Manchester Evening News.
“He is such a talented player on the ball. He has definitely lifted spirits in the dressing room and especially in training.
“We want to impress and show him that we are what we are,that we are one of the best teams to be at.
“He will have an impact in the future. There are no two ways about that. He will be a fantastic player for Manchester United, hopefully for many years to come.”
Mata enjoyed a great two years with the Blues after joining from Valencia in the summer of 2011 and going onto win the FA Cup and Champions League that season.
The following year the Spain international was hugely influential in the west London club’s Europa League triumph and was voted as the Player of the Year for both of those campaigns.
However, the return of Mourinho as boss saw Mata fall down the pecking order and the attacking midfielder managed just 14 appearances in all competitions this term before leaving for Old Trafford.
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