The Mexico striker, who joined United from Chivas de Guadalajara in 2010, has made an instant impact at Old Trafford, scoring 20 goals as the Red Devils claimed their 19th league title last season.
And the 23-year-old has been handed a new long-term deal with the Red Devils as a reward for his flying start to his United career.
â€œPlaying for Manchester United has been a dream come true for me,” said the forward. “I never expected my first year to go so well and Iâ€™m delighted to commit my future to United.
“To win a title and appear in a Champions League final was fantastic. Iâ€™m looking forward to helping my team-mates as we bid to win more trophies for this great club.â€
Manchester United boss Sir Alex Ferguson has heaped praise on the striker following his impressive impact at Old Trafford.
“The last player I remember making an impact as big and as quickly as Javier is Ole Gunnar Solskjaer and he reminds me of Ole a lot,” said Ferguson.
“His talent for creating space in the box and his finishing ability mark him out as a natural goalscorer. Off the pitch, he is a pleasure to manage. He works very hard and is a popular member of the squad.â€
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