Neck and neck in the finishing straight, the two contenders in the title race are not so much sprinting for the line as staggering, a la Jim Peters.
Fatigue has sapped strength and form, and what should be a test of skill and resourcefulness instead boils down to the survival of the fittest. United are still clear favourites, a superior goal difference probably more of an advantage than their game in hand at a time when another match comes as one more trying obstacle to overcome.
Tired mentally, as well as physically, the leaders had no complaints, for once, about their 1-0 defeat at Wimbledon on Saturday when they were again unrecognisable as the barnstorming team who threatened to settle the championship by Christmas.
The not-so-dirty Dons out- fought them, which was not a surprise, but also out-thought them, which was. Joe Kinnear is too shrewd a manager to make the same mistakes twice, and had learned valuable lessons from a comprehensive 3-0 defeat in the fifth round of the FA Cup.
Wimbledon had attacked the best team in the country that February day, and were destroyed by their speed on the counter. This time they would play a more cagey, defensive game, clogging up the midfield and doing the breaking themselves. It worked a treat. Their wingers denied space and a decent share of possession, United were stymied and made to look ordinary.
Crafty stuff by Kinnear, who is alone in winning two Manager of the Month awards this season. One of his predecessors once said he thought tactics were little white mints, but the Crazy Gang have always been big on kidology, and much smarter than they like to let on.
They beat Liverpool in the Cup final, against the odds, by cleverly deploying Dennis Wise to mark John Barnes out of the game, and more thought than meets the eye goes on behind all that macho posing.
Some would have it that their most potent weapon is Vinnie Jones' ballistic throwing, which Tim Flowers, for one, says is more difficult to combat than any free- kick or corner. In fact, their strongest suit is a collective mentality which would make the Musketeers look like selfish loners, followed closely by a tactical nous enabling them to make the most of modest resources.
They are a high-morale bunch, as evidenced by the high fives which salute every telling pass or tackle. They are also a better football team than they are given credit for - witness their 4-1 drubbing of Blackburn last month, and the four goals they put past third-placed Newcastle United in February.
To complete a hat-trick of victories over the top three, they adopted the 4-5-1 formation favoured by more fashionable passing teams. Dean Holdsworth, their principal striker, was withdrawn to the right side of midfield to leave Ryan Giggs and Denis Irwin with nowhere to run. Marcus Gayle helped Gary Elkins to do the same to the bafflement of Andrei Kanchelskis and, denied their usual outlets, United were left passing the ball to their central defenders, which was the object of the exercise. Kinnear said: 'In the Cup they didn't just beat us, they murdered us, and I thought then that the only way to play them was with five across the middle.
'It was a case of shutting off all the avenues to Giggs and Kanchelskis. I thought the best way was to let their centre-halves have it. They wouldn't cause us as many problems as the others.'
Spot on. Bristling with determination and legitimate aggression, Wimbledon might have scored after only four minutes, when John Fashanu, who played the lone striker's role to perfection, burst past Steve Bruce and Gary Pallister, but delayed a split second too long over his shot, allowing a snaking foot to thwart him in front of goal.
Amends were made midway through a scrappy first half, when Peter Schmeichel's reputation as the world's best goalkeeper suffered further self-inflicted damage. Distracted by the prospect of a bash from the oncoming Fash, Denmark's player of the year took his eye off Elkins' left-wing cross and allowed the ball to bounce free of his grasp. The Wimbledon captain put one of those garish red boots to profitable use at nudging range, and United were in trouble. Again.
Their reponse was to up the tempo in the second half, but Giggs, again out of sorts, shot weakly with Kanchelskis and Mark Hughes better placed to his right, Hans Segers made a useful save from Dion Dublin and Brian McClair volleyed over from 15 yards. When Paul Ince did manage to get the ball in the net, with four minutes left, he fouled the goalkeeper in so doing.
Wimbledon defended with discipline and tenacity, and Fashanu, who seems to have brought the rolling maul, as well as rainbow size nines to football, might have had a second at the death when he grappled his way past Pallister, only to shoot wide.
Alex Ferguson was determined to look on the bright side. It could have been much worse, after all. Blackburn had lost, too, and so, if anything, United had strengthened their position by improving their advantage in goal difference by one.
The two Cup games against Oldham Athletic had taken their toll, and his players had looked jaded, but they now had a week in which to recharge their batteries before playing Manchester City at home on Saturday.
'That's not a bad game to have,' Ferguson said. 'For 90 minutes we can put the League out of our minds. Some would rather win the derby.'
Another performance like this, and United could lose both.
Goals: Fashanu (22) 1-0.
Wimbledon (4-5-1): Segers; Barton, Scales, Blackwell, Elkins; Holdsworth, Fear, Jones, Earle, Gayle; Fashanu. Substitutes not used: Perry, Blissett, Sullivan (gk).
Manchester United (4-3-3): Schmeichel; Parker (Dublin, 73), Bruce, Pallister, Irwin; McClair, Robson (Sharpe, 63), Ince; Kanchelskis, Hughes, Giggs. Substitute not used: Sealey (gk).
Referee: T Holbook (Walsall).