Keegan was fiercely critical of Tony Jimenez, who was head of recruitment during his second spell at Newcastle, claiming that he refused to sanction the transfer of Luka Modric amongst others.
However, Jimenez has now hit back with a number of prominent players whom Keegan turned down.
"The moment you questioned him he lost the plot. During that window we offered him the players that we were working on when we thought Harry Redknapp was coming as manager - Jermain Defoe, Peter Crouch, Lassana Diarra - and he said none of them were good enough," Jimenez told 'The Times'.
"The other player we were really keen on was Daniel Sturridge. He said he'd had him as a kid at Man City and that he wasn't good enough for League One.
"He didn't want Hatem Ben Arfa or Karim Benzema either. We asked Kevin for a list of players for every position, bearing in mind he had £25million to spend. Our list included Benzema and Ben Arfa, who were young players at Lyon, as well as Samir Nasri.
"Kevin took one look and called them all chancers. His list was David Beckham, Frank Lampard, Ronaldinho, Kaka, among others. We added their transfer value up and it was £399m, plus £100m in wages."