Real Madrid are ready to pounce after Danilo pulled out of new contract talks with Porto yesterday.
The Br azilian wing-back is a top target for Real, along with Barcelona and Liverpool.
A Bola says Porto have failed to extend Danilo's deal a further 12 months, but the defender has rejected the terms.
The wing-back is tied to the Portuguese giants until 2016.
Real have already registered their interest with Porto and are waiting to open talks over a fee for Danilo.