Chelsea will return to Everton with a fourth and final offer for defender John Stones which could potentially be worth £40m, according to a report.
The England international submitted a transfer request today but the Toffees reiterated earlier this week that they will not sell the 21-year-old to the Premier League champions.
Jose Mourinho's side have already had three bids rejected for the defender, the third of which was reported to be worth in the region of £30m, and are thought to be undeterred by Everton's firm stance.
However, The Guardian claims that Chelsea will lodge a fourth offer of around £35m with add-ons to take it to £40m, a figure which is double their initial valuation of the player.
If Stones does leave, Everton would be left with just one senior centre-half in Phil Jagielka, with only a week remaining to find a replacement.