The Sun says he hopes to wrap up a £27million transfer for football's most wanted man within the next few days.
It will come as a crushing blow to City. They believed their massive financial clout had swayed the Chilean winger, 22.
But agent Fernando Felicevich said: "An agreement with City? Sanchez's future is still very much wide open.
"We are working on it and, after meetings with City, we have other new appointments."
The 19-time champions are increasingly confident of getting their man, even though £27m is about £4m more than they had originally hoped to pay.
But they have had to up the offer to beat off Barca and City.
The crucial factor in United's favour is that the player himself far prefers the idea of a move to Old Trafford than a switch to Eastlands.