�Former Arsenal midfield star Steve Williams believes this Sunday’s big clash with Manchester United has taken on “must win” proportions following defeat at Swansea.

The Gunners now trail fourth place Chelsea by six points while Spurs and the two Manchester clubs are seemingly in a three-way fight for the title with leaders City 15 points ahead of Arsenal.

And as his old club’s inconsistent form continues with their second league defeat of the New Year after their 2-1 loss at Fulham on January 2, Williams claims Arsenal must start a winning run this Sunday – or face the prospect of no Champions League football next season.

"Last week's defeat didn’t help matters did it, but then when is a defeat ever a good thing?" said the former Gunners hard man.

"The only thing I can say at the moment is that all the other teams are all capable of cancelling each other out. And Manchester City may be top but they have not exactly been in title-winning form in the past few weeks.

"Liverpool can beat Chelsea who can beat Spurs who can beat City who can beat United... that's the reality. That's how it is. These teams will all take points off each other, but from the perspective that matters – an Arsenal perspective – it is not a good thing when you start relying on others to help you out.

"In my experience, when that happens then you can come unstuck."

But Williams believes Arsene Wenger’s stuttering side can begin to make amends with victory over United at Emirates Stadium – as long as they don't think about that 8-2 result in the summer.

"It is always a must win when you play United, I suppose. But in this case it really is for Arsenal because they are starting to trail the leaders a little too much now," adds Williams, an Arsenal fan in his youth who played for the club between 1984 and 1988.

"I hate the fact Spurs are doing well but that's how things are at the moment. That said, it’s only January. Let's concentrate on the club that matters – Arsenal.

"We need to get a run of wins together and at home we should beat anyone no matter of reputation or league position. I never once took to the field at Highbury expecting anything less than victory.

"And that 8-2 should not make one bit of difference to anyone in an Arsenal shirt. They are at home, in a great stadium, packed to the rafters, with 60,000 expecting them to win. And I believe they will – absolutely.

"Can they then go on a run where they win nine out of their next 10? I'm afraid, I'm just not sure with this team. The talent is there, but they must strive for that consistency."

Williams, a combative midfielder who married fight with flair, is looking to the midfield to take charge on Sunday.

"Something is missing at the moment. Jack Wilshere will make a big difference when he eventually returns. But the job of the midfield is to win the ball and then help set up chances for our strikers.

"That's what I did. That's what Patrick Vieira did. That's what Roy Keane did at United. I want to see more of that from our midfield – they need to stop the other team playing and then be creative at the other end.

"Our wingers also need to start upping their game. We don’t get the ball in the box enough, we don't cross the ball enough. And you're not going to score enough goals if you don't get the ball in the box in the first place."

But talk about a lack of ambition – an accusation pointed at the Arsenal board and Arsene Wenger by some supporters – and Williams bristles, displaying that legendary anger he so often displayed in the Arsenal engine room back in then 1980s.

"Don't even go there. Don't talk to me about this lack of ambition argument. It is rubbish, total and utter rubbish," he snaps.

"Things are going right on the pitch, granted. We want to be further up the table – well, at least above Spurs which is never normally a problem – but Arsenal remain ambitious.

They were when I joined them in '84, even if the team wasn’t doing great then, and they are now.

"We've a great stadium and lots of money and could probably afford to go out and buy Lionel Messi if we wanted, because I’m sure the finances are there. Actually, that wouldn’t be a bad idea..."

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