Chelsea have been linked with a move for Stones all summer and despite the Toffees rejecting three bids for their prized asset, Chelsea are all set to test the waters with a fourth and final offer.
Chelsea are in desperate need of a centre back and despite their interest in Garay, Stones remains the prime target for the Blues.
It is believed that Everton are already looking at replacements for the England defender and Christian Zapata is a target for the Toffees.
Although Roberto Martinez is unwilling to let go of Stones and has claimed that the player is not for sale, Everton are known to be willing sellers for the right price.
The Premier League Champions have made a poor start to the season and are keen to get back on track with a few new signings.
After signing Pedro from Barcelona, Mourinho is now keen to wrap up the deal for John Stones.
The Blues are also preparing a mega money offer for Juventus midfielder, Paul Pogba.