Beaten at home by Liverpool and held at Craven Cottage in their previous Premier League matches, Chelsea somehow overcame their faltering form to contrive a morale-restoring win over the leaders, reviving their almost extinguished hopes of defending the title and spoiling a historic occasion for Ryan Giggs, who managed to collect a rare booking while equalling Sir Bobby Charlton's league appearance record for Manchester United.
It was a very English match, the ebb and flow interspersed with bruising collisions that would have halted the action in any other major European league but were allowed to pass by without action from the referee, Martin Atkinson, who nevertheless made the key decision of the match when he judged Chris Smalling had felled Yuri Zhirkov late in the second half.
David Luiz had brought Chelsea level soon after the interval. The Brazilian, who cost just under half of Fernando Torres's fee, is looking not just the better buy but the more effective striker. The first-time shot with which the centre-back laid the foundations for victory was hit with an alacrity that the Spanish striker must have envied. And with his weaker right foot, too.
A "must-win game", John Terry called this one in his programme notes, suggesting that a victory over United and another in their game in hand would push Chelsea into third place in the table. As calls to arms go, this one was sounding a little less than effective on the half-hour as Wayne Rooney turned through 180 degrees outside the home penalty area before striking a superbly accurate shot between Petr Cech and the near post.
Terry's words, surely boosted by the knowledge that United had not won in this part of west London for nine years, were looking a lot more substantial 50 minutes later when Frank Lampard smashed a penalty down the middle to give Chelsea the lead. Zhirkov had pushed the ball through the legs of the otherwise immaculate Smalling and gone to ground with little visible assistance. It was Atkinson's 11th penalty and 10th red card of the season, the highest totals on both counts of any Premier League referee.
On the fifth anniversary of the death of the much-loved Peter Osgood, the initial focus of attention, at least among those not preoccupied with the need to howl "Shoot!" every time the ball reached the hapless Ashley Cole, had been on Chelsea's strikers. Once again Didier Drogba found himself consigned to the bench, not a place he believes to be his natural home. His haul of 93 goals in 191 league appearances compares favourably with Osgood's 105 in 289.
Torres, Roman Abramovich's £50m purchase, took his place in the starting line-up, yet to score a goal in Chelsea's colours although destined to celebrate a league win for the first time. On form, he would come closer to the ideal of Osgood – upright, elusive, velvet-footed, with an inventive eye for a strike and a shrewd, economical ability to link the play of less gifted men – than many of those who came between them at Stamford Bridge. With Nicolas Anelka spending most of his time stationed on the right wing, and Drogba having to wait until the hour mark to replace the Frenchman, Torres had plenty of space to exploit, but he again failed to make a mark on the match. "I don't ask him to score," Carlo Ancelotti said afterwards. "I ask my strikers to play for the team."
Some Chelsea anxieties will be alleviated by this adrenaline-fuelled victory, but the result is unlikely to obscure the evidence that too many of Ancelotti's players have lost form with a mystifying simultaneity. Where has Frank Lampard, the 30-goal-a-season midfield player, gone? Trapped in the swamp between defence and attack, and receiving scant assistance from a Michael Essien seemingly shorn of his prodigious power.
The real Lampard would have scored not just from the penalty spot but with a free-kick in the 40th minute, struck low and hard from outside the area, provoking a fine double save from Edwin van der Sar. The real Essien, driving towards the United area five minutes later, would have found a way round, past or through Nemanja Vidic's cold-blooded obstruction, for which the Serb received the first of two well-merited cautions. Florent Malouda's virtues are simply lost without trace, making Ramires, an object of scorn earlier in the season, the most dependable figure in a spluttering engine room.
At least the athletic David Luiz was providing a spark of hope. In the early stages he made his presence felt on both sides of the pitch, evoking the memory of Ricardo Carvalho, Terry's previous partner, as he shepherded a fast-breaking Rooney on the left and deftly halted the trickster Nani on the right a couple of minutes later.
Booked after 60 minutes for a foul on Rooney, the Brazilian newcomer showed further signs of rashness as the match boiled up and might easily have preceded Vidic into the dressing-room for a couple of indiscretions that evaded Mr Atkinson's attention. This, however, was a night on which Chelsea rode their luck, and galloped home.