Chelsea have reportedly had a £20m bid for England international John Stones rejected by Everton.
The 21-year-old has been the subject of rumoured interest from the Premier League champions this summer, as a potential long-term replacement for current centre-back duo John Terry and Gary Cahill.
According to Sky Sports News, Chelsea have now made an official approach for the former Barnsley defender, who cost the Merseyside outfit just £3m when signing two years ago.
It is claimed that the Blues may make a fresh approach in the coming days or instead turn their attention elsewhere, with Real Madrid's Raphael Varane among those to have been linked with a switch to Stamford Bridge.
Meanwhile, Toffees boss Roberto Martinez has rejected speculation that he is interested in making a move for Manchester United's Jonny Evans.
