Premier League - United roar back to hold Villa
Ashley Young broke the deadlock from the penalty spot in the 72nd minute, and Marc Albrighton swiftly doubled his side's lead as the hosts looked to have put a hefty dent in United's pursuit of Chelsea at the top of the table.
Sir Alex Ferguson threw on Federico Macheda, and within eight minutes of his introduction the Italian pulled one back, before Nemanja Vidic headed United level five minutes from time to salvage an improbable point.
Gerard Houllier was forced to field a side bereft of eight first-team players, with diminutive rookies Barry Bannan and Jonathan Hogg forming an unfamiliar central midfield partnership, while Ferguson reverted to 4-4-2 with Javier Hernandez in attack alongside Dimitar Berbatov.
The first clear-cut chance of the game was carved out by the visitors in the 17th minute: Berbatov beat the offside trap to meet Hernandez's through ball, but the forward fired wide in very shoddy fashion to hand the hosts a real reprieve.
Villa enjoyed an increased share of possession as the first half developed, and Edwin van der Sar was forced to make a sprawling save down low to his right to deny Young, whose rasping volley from the edge of the United box on the half hour mark looked destined for the corner of the net.
Just a minute later United should have broken the deadlock themselves as Nani found Patrice Evra with an incisive drill straight from the training ground from a regulation free-kick but, inexplicably, no United player made a run to convert the Frenchman's stunning delivery across the six-yard box.
Villa were on the front foot at the end of the half, and Stewart Downing was almost wheeling away in premature celebration two minutes before the break as his piledriver from the edge of the box was somehow deflected wide of the near post by Rio Ferdinand.
Villa began the second half with real purpose and passion: first Park Ji-Sung was bundled off the ball by Albrighton, whose pinpoint cross was met by Gabriel Agbonlahor's head inside the United box, albeit with insufficient power; then the forward had a shot deflected wide by Ferdinand seconds later.
There was a touch of acrimony in the 53rd minute as Nani was booked for leading with his elbow in a challenge with Stephen Warnock on halfway: the reaction was one of unbridled fury from the Villa players, and replays suggest the Portuguese was perhaps fortunate to remain on the field.
Seconds later, the hosts were almost rewarded for their electrifying start to the second half as Downing forced his way down the left and picked out Albrighton at the back post with a pinpoint delivery, only for the winger to head wide from close range.
James Collins came within a few inches of netting the opener in the 67th minute as the forward rose imperiously to rattle the crossbar with a powerful header. And, if Houllier was rueing his side's luck after that, his frustration was compounded seconds later as Agbonlahor beat Ferdinand to a loose ball inside the United box and struck the near post with a fierce shot with Van der Sar comprehensively beaten.
But Villa's incessant pressure was finally rewarded in the 72nd minute as Young dispatched his penalty kick with aplomb after he was bundled over clumsily by Wes Brown in the United box.
Ferguson swiftly responded with a double attacking change as the ineffectual Hernandez and Berbatov were hauled off to allow Macheda and Gabriel Obertan a chance to make an impact. But it was Villa who inflicted further damage as Downing broke at pace down the left, before Albrighton capped off a stunning counter-attack with an opportunistic finish at the back post.
Macheda's introduction did force the desired effect for Ferguson five minutes later, however, as the Italian received a pass from Darren Fletcher on the edge of the Villa box, then lashed an unerring strike into the top corner of the net.
And four minutes later United were level in dramatic fashion: Nani jinked inside Luke Young out on the left, then whipped over a stunning delivery which picked out Vidic at the back post, who managed to head the ball inside the far post with precision.
Both sides pressed for the three points in an enthralling finale, but it was the hosts who were the more disappointed with the point after having seen their lead so swiftly eroded.
Villa remain unbeaten at home as a result of the draw, while United have yet to be defeated all season as Ferguson's side move to within three points of Chelsea, albeit having played a game more than the league leaders.