Roy Keane, already considered an enemy at Arsenal following his bust-ups with Gunners legend Patrick Vieria, has started a fresh war of words with the club.
The Sunderland boss, whose side held Arsene Wenger's men to a 1-1 draw last weekend, says all the talk of Arsenal's youth policy is over-the-top.
Keane says Wenger does not deserve all the credit for their young stars because he has bought them rather than helped through the club's youth system.
He said: "The word on the street is that Arsenal have a group of kids coming through that will be absolutely outstanding.
"But you go on about the kids coming through but a lot of them have been bought from other clubs, not through the academy at Arsenal. It's the same with Chelsea."
The Gunners paid £10 million to sign Theo Walcott, then 17, while Cesc Fabregas was snatched from Barcelona's youth system. New recruit, 17-year-old Aaron Ramsey, was brought in this summer after impressing for Cardiff City.
Meanwhile England winger David Bentley, who did come through the youth system, was considered surplus to requirements and sold to Blackburn, who then sold him to Spurs for £15m.
During his time at Manchester United Keane saw manager Sir Alex Fergusson bring the likes of David Beckham, Paul Scholes, Gary and Phil Neville, Nicky Butt and Ryan Giggs through the club's much-envied youth system.
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