LONDON:  John Terry has been one of the greatest players in Chelsea’s 110 years. He is not the quickest player in the world but he has more than made up with his tackling, his heading, his reading of a game and his outstanding leadership qualities on and off the pitch.

He will be a tough act to follow. But Jose Mourinho has decided that Everton’s John Stones is the one player who might develop into such a successor. This is the reason the Blues are going back now, for a fourth time in five weeks, to try to force a deal within the transfer window.

Everton chairman Bill Kenwright has insisted that 21-year-old Stones, who has played four times for England so far, is not for sale this time around. But that was before the player asked for a transfer on Tuesday.

Chelsea have had three bids rejected, the most recent for £30m and they are expected to go to £35m before the English window closes at 1900 CET next Tuesday.

Stones signed a five-year contract only last August which means Chelsea will have to pay beyond the player’s value to buy him out. In addition, the best young English players also bear a price premium because of the ‘home-grown’ label – as Manchester City conceded in paying an excessive £49m for Liverpool’s Raheem Sterling.

The Stones saga is wearing down manager Roberto Martínez who has to deal with the same question at every press conference, before and after matches. But Martinez has merely underlined the qualities of the player by insisting that he has no qualms about picking Stones because the player can withstand the pressure.

Whether Martinez will maintain that mindset ahead of Saturday’s game against Tottenham may indicate whether he has decided to prepare, pragmatically, for a new defensive future.

Stones is understood to consider Stamford Bridge as the ideal venue at which to develop his career even though he will have to fight for his place against not only the intimidating Terry but fellow England defender Gary Cahill and the impressive Kurt Zouma.

He has not played for England at senior level since last September, instead having remained with the under-21 team who went to the European finals in Czech Republic in June. Stones suffered a head injury in training and was badly missed in the first two matches as Young England failed to progress beyond the group stage.

Stones is expected, however, to be restored to the seniors when Roy Hodgson names his squad on Sunday for the Euro 2016 qualifiers against San Marino and Switzerland. Coincidentally, Everton’s first game after the international break will be against Chelsea back at Goodison Park on September 12.