Everton goalkeeper Tim Howard believes in-demand centre-back John Stones can develop into a "brilliant" defender.
Speculation is rife that Stones will swap Goodison Park for Chelsea's Stamford Bridge before the transfer window shuts, but Everton manager Roberto Martinez is determined to keep hold of the 21-year-old.
Despite the uncertainty, Stones remains an Everton player and will feature against Manchester City on Sunday.
Howard, who has played alongside Stones for the past three seasons following the England international's arrival from Barnsley, said his Everton team-mate has the potential to become one of the world's best.
"John is a very good player," Howard told Soccer Saturday via Sky Sports.
"As young as he is, he's full of confidence, but he's not arrogant.
"He's a strong presence, which is exactly what you want a central defender to be.
"I think he'll be brilliant, he's got all the qualities but he needs to play another hundred games before you can say how good he's going to be."
Stones has made 46 Premier League appearances since moving to Merseyside from Oakwell in 2013-14 for a fee in the region of £3million.
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