United travel to the Etihad Stadium on Sunday and will face a City side who have not been beaten in the Premier League this season.
Aguero has played a key role in Citys impressive start with seven goals in the league.
I only fear when I play against him, Mourinho said when asked about Aguero.
I admire because of his fantastic qualities.
There are little things in his game that Im not a big fan of.
But the numbers speak by itself, how many goals he scores – and is not about scoring goals in one season.
Is scoring goals in one career, is scoring goals [in] like the Spanish league.
When asked what he didnt like about Agueros game, Mourinho replied: I keep for me.
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