Before Roman times, there were United and Arsenal, Fergie and Wenger, north and south; the two clubs sharing titles, their teams trading punches, the managers exchanging verbal darts. In five seasons out of six they were the top two in the Premiership but Chelsea have broken that cosy little duopoly for the past two years and will do so again this time.

They are out of Arsenal's reach and a couple of months ago, 17 points clear, seemed to be beyond United's too. Now the gap is down to seven and ahead of needle matches this afternoon at first Stamford Bridge (Chelsea v West Ham) and then Old Trafford (United against Arsenal), Alex Ferguson finds his nostrils twitching. Suddenly United believe they have a sniff of a chance again.

One of the many advantages of having a manager who has been around for 20 years is that he tends to have seen just about everything there is to see. Ferguson has experienced it all, bought the t-shirt that says 'Champions' and the metaphorical one with a Gorbals expletive on for titles thrown away.

Being the obsessive that he is, Alex has even clearer memories of championships lost than won. How about this for total recall? "I go back to 1992. We lost a seven-point lead to Leeds by losing three and drawing one in eight days. We lost a goal in the last five minutes to Luton on the Saturday. We also got two players injured in the match.

Then we went into the Nottingham Forest game on the Monday and battered them, but got beaten 2-1. On the Wednesday we had other injuries for the trip to West Ham and we lost 2-1. We had a few players back for the visit to Anfield at the weekend, but it was the sudden impact of drawing one and losing two, it really killed us."

And so on, and on, with detail provided of all the players who were injured in the crucial games. But the relevant point, which he eventually reaches, is this: Our form had gone. That is why I say, if your form is good in April then you have a chance. The infinitely more pleasurable experiences of 1996 and 2003 when Kevin Keegan's Newcastle and then Arsenal were hauled back from apparently impregnable positions and passed on the run-in, are currently sustaining United's faint hopes.

Their form this April, going into what Eliot called the cruellest month, is superb, on the back of eight successive victories, which is precisely why the crafty old fighter is sending the message south just as Chelsea have a little wobble. "I think the team as a whole have done well since we won the League Cup [in February], " he said. "Their form has been excellent and they're all playing well. I can't fault anyone. That kind of form must give us a chance."

Exactly a year ago, Arsene Wenger thought Chelsea might just be catchable, with his team on a long run of victories in all competitions. Yet the one match they failed to win out of a dozen was the one that mattered most, an anti-climatic draw at Stamford Bridge in late April. Jose Mourinho's side maintained their nine-point advantage and tied up the title 10 days later.

United will have a similar opportunity in London on 29 April, the penultimate weekend of the season, but only if they can further reduce the gap before then; which means that beating Arsenal today is essential. "We are in a closing position, " Ferguson said, "and hopefully if they do make another mistake and we can win our game [today], it might be a real test then."

Recent meetings offer his club every reason for optimism, whether or not West Ham can shock Chelsea the way they did Arsenal at Highbury a couple of months ago;

not for four years have Arsenal had the better of United in the Premiership. Their followers will doubtless sing the version of a favourite ditty that runs, "We won the League/At Old Traff-ord", but it happened in 2002, since when there have been three defeats and four draws. Even last season's FA Cup final success was on penalties after being outplayed. "We know how to play against Arsenal, " Ferguson was bold enough to point out on Friday, presumably meaning get among them from the first minute and harry them relentlessly, taking advantage this time of a clear week's rest and preparation while the opposition were away in Europe.

The drawback, of course, is what Wenger's team have achieved over the past month, reacquainting themselves with heights that were not expected of such an inexperienced squad for some time to come . . . if at all. "What Arsenal have done with a young team is exceptionally good, " Ferguson conceded. "I don't think anyone expected that. I certainly didn't and probably Arsene Wenger himself didn't. I don't think Italian football is at its best, but they cruised through against Juventus."

The Old Lady provided no sort of threat. It is inconceivable that the old fellow who has seen it all will submit as tamely.

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