Chelsea fear both Manchester clubs are secretly plotting moves to snatch John Stones from under their noses.

The Barclays Premier League champions are pursuing the England defender having already had two offers rejected by Everton.

Jose Mourinho is set to return with a third offer in the region of £30million before the transfer deadline, despite Roberto Martinez's insistence that Stones is not available at any price.

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Chelsea are worried that both Manchester clubs want to steal John Stones from under their noses

Chelsea are set to return with a third offer of about £30million for Everton defender Stones

Chelsea are confident of swiftly agreeing personal terms with the centre-back, believing Stones wants to join.

However, there is growing concern at Stamford Bridge that they will not have a clear run at the former Barnsley man.

Members of the Blues hierarchy believe City and United will table their own offers for Stones, if and when the Toffees accept a bid from them.

It has been indicated to Blues chiefs that their Premier League rivals are merely waiting to see if Everton can be convinced into selling their star defender before making moves of their own.

Sources claim City were plotting a similar tactic with United target Sergio Ramos.

Stones' future looks likely to be a pertinent issue during the closing days of the transfer window, with Chelsea fearing a late twist in the protracted saga.