Roberto Martinez has spoken out in defence of Ashley Williams, insisting the Swansea defender is "not the type of footballer" who would intentionally strike a ball at an opponent's head following Sunday's incident involving Robin van Persie.
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Manchester United manager Sir Alex Ferguson reacted angrily when Williams fired the ball at his striker from close range - apparently to make a clearance although the whistle had already gone for a foul in United's favour - during Sunday's 1-1 draw at the Liberty Stadium.
Ferguson asserted that Van Persie "could have been killed" and that the FA should heavily sanction Willams, who maintains his innocence and said he has tried to apologise.
Wigan Athletic manager Martinez signed Williams during his time in charge of Swansea, and insists the captain of the Welsh club would not have done such a thing on purpose.
"You see the incident and it is a very, very dangerous situation,'' Martinez said. "If you see one of your players with a bang on the back of the head it is really dangerous and it can have bad consequences. You can understand that.
"I signed Ashley Williams for Swansea and I know his character inside out. I can guarantee you without even looking at the incident that he is not a nasty footballer. He is a winner and fully committed, a leader and a captain, and I don't for one second doubt that he did not do that on purpose.
"It is an action of the game. He can show frustration - it is an emotional game and it is very unfortunate that it hits Van Persie in a part of the body where he could have been hurt heavily, and you don't want to see that. But from my point of view, I know Ashley Williams really well - when you sign a player you find out about a player and I can guarantee you he is not the type of footballer who would do that on purpose."
Another of Williams's former manaers at Swansea, Brendan Rodgers, also offered his backin for the Wales international.
"I think more has been made of it than what it actually was,'' Rodgers said. "When you slow it down and look at it 20 times it does not look good for Ashley.
"But I know the player well and it is just that split-second when you can see he is trying to clear the ball and unfortunately hits Van Persie right on the back of his head.
"Of course, it looks dangerous but knowing Ashley he won't have meant it, knowing his character that won't have been intentional."
Queens Park Rangers manager Harry Redknapp questioned Ferguson's comments and said he has seen many more serious incidents happen during matches.
"I don't see how he was going to be killed," he said. "He kicked the ball at him. I have seen worse things on a football pitch."
Newcastle boss Alan Pardew understood Ferguson's reaction but said that with hindsight the United manager might not be so angry.
Pardew said: "He genuinely felt that, I should think, at the time. You do. If one of your players gets hurt or you think he was in danger, you are going to protect him.
"I think the one with Van Persie was perhaps not as bad as Alex at first imagined. Sometimes from the sideline, it looks a lot worse at the time. I'm not sure whether there will be action taken for that."
Celtic boss Neil Lennon, however, said he arred with Ferguson that Vna Persie could have hurt in the incident and branded Williams's actions "disrespectful".
"I don't like to see that,'' Lennon said. "I think it could have been avoided.
"Maybe Ashley has kicked the ball away and it's a split-second reaction.
"But I see that quite a lot and players who are on the receiving end of it think it's disrespectful.
"I don't like to see that in the game and Sir Alex is right, Van Persie could have been hurt and it was totally unnecessary.
"It's an unwritten law, one of those in the game, it's just something that you don't do. For me it's, I wouldn't say cowardly, but it's cheap, put it that way."