ALEX FERGUSON can deliver what could be a knockout blow to Arsene Wenger if he can shake off the impact of back-to-back defeats by Chelsea and Liverpool with a win over Arsenal in the FA Cup.
That's what's at stake at Old Trafford tomorrow. It's not just an FA Cup tie and it is ironic that these two sides should meet in a competition which Ferguson and Wenger have done much to devalue over the years at a time when both managers are under such pressure.
If Manchester United win, Ferguson will crow and praise the romance of the Cup. If he loses? Well, it's only the Cup after all.
If Arsenal win, Wenger will sell it as a sign that his team is good enough to win trophies. If he loses, well it's only the Cup after all.
But Wenger is on the ropes at the moment and if Manchester United do win, I can see Arsenal's title challenge falling apart in short order.
Wenger has been promising great things for this Arsenal team for the past four or five seasons and it looks to me as if his trophy cabinet is going to be empty again this time around.
That would be a big blow to Arsenal fans who thought that this season would be the one when their team delivers – maybe not in the Champions League but certainly in the Premier League.
They have been very patient with Wenger and I don't think that will change. He has given them too many good memories for any public signs of displeasure.
But, as I always say, managers build up credit in the bank in the good years and spend it when the results take a dive. I'm not sure Wenger has much left on deposit.
I can't remember a time when Ferguson and Wenger shared anything other than an intense dislike for each other but they are brothers in crisis at the moment.
Both men are facing censure from the football authorities and they will eye each other across the Old Trafford dugouts knowing that they have both suffered significant setbacks in the past few weeks.
Defeat in the FA Cup for either team will be costly but much less so for Ferguson. Manchester United are still in the Champions League and still leading the Premier League.
Sure, he won't be at all that comfortable about the way his team has been playing and he knows he has a big job on his hands in the coming months but he thrives on these circumstances.
I don't imagine Ferguson's problems with the English FA will amount to much but I do sense that we have reached a tipping point with the constant moaning and complaining about referees, which is now endemic in the game. Wenger is still whingeing three days after he was given another football lesson by Barcelona and how he can persist with the deluded notion that it was the referee – and not the extraordinary skills of Iniesta, Xavi and Messi – who undermined Arsenal's Champions League hopes is beyond me.
There has been a relentless flow of completely one-sided criticism of match officials from Wenger for a long, long time but I think people have had enough now and UEFA have a chance to make a stand on the issue.
Whether they will be brave enough to do what needs to be done and hit Wenger with a big suspension remains to seen. UEFA won't do anything with technology to help referees but maybe they will see this as an opportunity to make a point. Wenger has argued that he has no case to answer and has already said that he sees no reason to apologise to Massimo Busacca, the match referee at the Nou Camp.
In fact, he thinks UEFA and Busacca should be apologising to Arsenal football club, which provides us with a very revealing insight into just how blind Wenger is to his own flaws.
Both he and Ferguson are the senior men in the Premier League and in European football. They should be setting high standards. They are actually doing the opposite and creating an environment for other, lesser managers to copy them and persecute match referees – while ignoring their own responsibilities.
Funnily enough, I'm convinced that Wenger believes everything he says and is so blinkered that he cannot see how ridiculous he looks and how mealy mouthed he sounds in defeat.
But I think Ferguson plays the system like a musical instrument and, let's be honest, he has ruled the roost for years, throwing his weight around when he feels there is a point to be made or an advantage to be gained.