Liverpool, Walker was adjudged to have brought down Sadio Mane in the penalty area and the spot-kick was converted by Mohamed Salah.
Speaking at half-time on Sky Sports, Keane said Walker was an 'idiot' and added: "he's a car crash, he keeps making these types of mistakes and is rightly punished for it." City have reportedly made clear to the broadcaster their displeasure at Keane's searing comments and writing in his blog, Keys hit out at the ex-Manchester United captain. "We were always very much aware that if we were going to criticise then it had to be done constructively.
That we could offer both explanation and education," Keys wrote."Andy Gray did that better than anyone else - and he’s still doing it.
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