BILD says Bayern Munich fear Coman could join United this summer.
Coman's current deal with Bayern expires in 2023 and the German champions are keen to tie him down to a new contract.
However, Bayern are concerned the French winger could have his head turned by United.
The report says United would be willing to pay the 24-year-old in the region of £260,000 per week to lure him to the Premier League.
And now it's emerged City are prepared to compete with United for Coman's signature this summer.