Adams says there is a dearth of top quality defenders and that is why Manchester City were willing to pay £47million for the England centre-half.
Ex-Arsenal skipper Adams makes the claims in his new book Sober which delivers a damning verdict on general standards of defending.
Adams even compares Stones to former West Ham and Blackburn defender Tony Gale, who had a 600-game pro career and won the Premier League title but was never capped.
It perhaps serves as a wake-up call for England generally as Stones is now seen as one of the nation’s best prospects despite a difficult first season at the Etihad.
Adams said: “John Stones was hailed as a great new English central defender, first at Everton and then at Manchester City.
“I have always had my doubts about him; considered him to be average in all honesty, despite this hyping of him as a ball-using defender. I saw him as a Tony Gale — a centre-back who passed the ball well, and was good enough to win a Premier League with Blackburn Rovers, but who did not win an England cap.
“Such is the dearth of English ball-playing defenders though, that Manchester City were willing to pay nearly £50m for Stones.”
Adams marshalled England’s defence in a golden era and partnered Sol Campbell, who also enjoyed a great career with clubs and country, for Arsenal.
The Three Lions also boasted John Terry and Rio Ferdinand in their ranks, before the Golden Generation gave way to the current crop.
Former England bosses Roy Hodgson and Sam Allardyce even toyed with bringing Terry out of retirement, such was their lack of options. And now Gareth Southgate may join the back three revolution for Saturday’s World Cup qualifier in Scotland
It would be the first time he’s used it in a competitive game, having tried it in the friendly in March.
Southgate could opt for a back three because he is short of candidates for a midfield anchorman role. With Jordan Henderson a long-term injury problem and Jack Wilshere having gone backwards this season, it just leaves Eric Dier.
So he will look to a back three as a way to give the team security, while also having options at wing-back.
It is a hot trend among Premier League teams after Antonio Conte used the system to lead Chelsea to the title this season.
England also have greater numbers in central defence – even if there are questions over the quality – with Chris Smalling, Stones, Gary Cahill and Phil Jones. Burnley’s Michael Keane is another to emerge, and even though he is out injured this time he did visit St George’s Park on Tuesday to show his support.