Mourinho dismissed conspiracy theories that he has talked up his interest in Wayne Rooney to try to destabilise Premier League champions United.
"I don't understand those theories because it is normal that we would want to strengthen our squad in every position," said Mourinho.
"We did it from the goalkeeper, we did it in midfield, in the creative positions, we did it in the striker's position where we have kept the players we had last year and a player returned from loan.
"It is basic and normal, and we want to give more quality to the whole structure. It is obvious that the striker position was a position we would try to improve."
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