Manchester United will surely be frustrated with their 1-1 tie against Swansea City, a game the Red Devils had plenty of chances to win. Following the game, however, Sir Alex Ferguson's frustrations with Swansea defender Ashley Williams seem to be far greater.

That's because Williams booted the ball directly into the back of Robin van Persie's head after the United striker was fouled and went down just outside of the box. As play was stopped, Williams kicked the ball and drilled van Persie, causing the striker to fly to his feet in an outrage and nearly incite a fight.

UPDATE: Monday, December 24 at 9:50 a.m. ET by Timothy Rapp

Despite Sir Alex Ferguson's pleas to the FA, the governing body has decided against banning Williams for kicking a ball into van Persie's head on Sunday.

From The Guardian:

The Football Association will not take action against the Swansea Citydefender Ashley Williams for kicking a ball at the head of Manchester United's Robin van Persie.

United's manager, Sir Alex Ferguson, called on the FA to ban Williams for a long time, claiming Van Persie "could have been killed" by the incident.

But the governing body will not instigate disciplinary procedures against the Wales international, who denied malicious intent.

---End of Update---

UPDATE: Sunday, December 23 at 12:55 p.m. ET by Timothy Rapp

Williams has responded to the incident and to Sir Alex's opinion on the matter, via BBC:

Everyone's going to have their own opinion. From my point of view, I tried to apologize on the pitch but obviously it all flared up. I kicked the ball in frustration, I'm obviously not trying to hit him square on the head. I tried to apologize but didn't get the chance.

Williams added he understood van Persie's frustration after being struck with the ball. For his full comments, be sure to check out the video at BBC.

---End of Update---

Here's the incident in question (GIF via footballtweet.lockerdome.com):

Ferguson didn't hold back when commenting on Williams' actions after the game (via Goal.com):

Well it was a foul on Van Persie, a clear foul, but then again, the referee has had one of those days and not given us anything. He had a shocking performance today.

I know he is a young referee but I was disappointed with that performance. The Van Persie situation, he clearly sees the incident.

He could have been killed. I think the FA has got to look into it—irrespective of him getting a yellow card, he should be banned for a long time, because that was one of the most dangerous things I have seen on a football pitch in a long time. Absolutely deliberate.

The whistle had gone, the game stopped and he has done that right in front of the referee. He could really have killed the lad.

It's hard to blame the United manager for seething after the incident. While there remains the slightest of possibilities that Williams' actions were unintentional, it certainly appeared as though he purposefully sent the ball into the back of Van Persie's head.

If that's the case, Ferguson is right—Williams must be banned, and the suspension should be a lengthy one. Van Persie could have been hurt badly, especially from that distance.

Normally, I might accuse Ferguson of hyperbole here or allowing his frustration with his team to fester after United saw their lead over rivals Manchester City shrink from six points to four. In this case, though, I think his anger is totally justified.

I would expect Williams to publicly apologize without admitting he struck Van Persie on purpose. I expect he'll say he kicked the ball in frustration, but never attempted to hit Van Persie, though kicking the ball in such close proximity to a fallen player was dangerous and in poor judgement.

We'll see if the FA buys that or takes any further action. I imagine we haven't heard the last of this situation, not by a long shot.