Legspin great Shane Warne on Friday continued his attacks on John Buchanan, saying former Australian cricket coach had "no idea" about coaching.
Warne - who captained Melbourne Stars in the 2012/13 Big Bash League with a coaching staff bursting at the seams including sports psychologist Jeremy Snape and team mentor Viv Richards - says coaching is for children, not for adults.
"Coaching is for 12-year-olds and not international cricketers," Warne told Indian reporters in Delhi.
"A senior player should receive mental support from the staff and needs to ensure he's thinking positive before a match.
"John Buchanan had no idea about coaching.
"The Australian team I was part of hardly needed a good coach. Even my 13-year-old son could decide when to bowl (Glenn) McGrath, (Brett) Lee or (Jason) Gillespie."
Warne retired from test cricket in 2007 with a then world record of 708 test wickets, while World Cup-winning and Ashes-winning coach Buchanan stepped down later that year and now works for New Zealand as director of coaching.
The coaching issue has been in the spotlight in the past two weeks.
Australian coach/selector Mickey Arthur banned four players from the third test in Mohali for failing to deliver homework assignments on time.
Vice-captain Shane Watson, one of four players who were suspended, returned to the side for Friday's fourth and final test in Delhi as skipper following Michael Clarke's absence with a back injury.
The decision by Arthur, Clarke and team manager Gavin Dovey to ban Watson, Usman Khawaja, James Pattinson and Mitchell Johnson has been lampooned by ex-players as schoolboy stuff.
Warne says booze and loud music in the changerooms are the best way to improve team culture and disciplinary issues.
Warne, who counts Clarke among his closest friends, refused to stick the boot into Arthur as others have done.
"Australia has many inexperienced players in its squad," Warne said.
"The teams I was part of took two tours (in 1998 and 2001) to realise how to win in India (in 2004)."
Warne said it would be unfair to blame Arthur for Australia's poor performance.
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