Aston Villa missed out on the chance to move top of the Premier League as they were held at home by Sheffield United.
Cameron Archer, sold by Villa to the Blades in the summer, stunned the hosts by opening the scoring in the 88th minute from close range.
Substitute Nicolo Zaniolo snatched a point for Villa with a header deep into stoppage time, but they could not find a winner.
Villa needed a win to go top for the first time since August 2011, having not led the table at this stage in a season for 25 years.
But despite dominating possession and chances, they remain behind leaders Arsenal on goal difference.
Leon Bailey had the ball in the net earlier in the second half but it was ruled out by the video assistant referee.
Villa had come close in the first half when United keeper Wes Foderingham saved low from Moussa Diaby before Ezri Konsa sent a stooping far-post header over from a John McGinn corner.
They were also frustrated by VAR, which corroborated on-pitch official Anthony Taylor’s decision not to award an 11th-minute penalty when Ollie Watkins was bundled over by Vinicius Souza.
VAR continued to deny Villa after the break, with Jacob Ramsey judged to have fouled Foderingham from a corner before Bailey swept home just before the hour.
And they were sucker punched in the 88th minute when Archer turned home Gustavo Hamer’s pull back from inside the six-yard box, before Zaniolo rescued some small consolation by beating Foderingham to Douglas Luiz’s 97th-minute cross.
Villa’s Christmas dreams dashed
The build-up to this game was dominated by talk of how a win would ensure Villa finish a day top of the Premier League table at least 18 games into a season for the first time since they led the way at Christmas in 1998.
A club-record run of 15 successive home league wins, including victories over Manchester City and Arsenal in their previous two matches at Villa Park, has ensured Unai Emery’s side are firmly in the title picture – but that run is now at an end.
Certainly United manager Chris Wilder treated this game like a visit to a title contender, with his side clicking into a 5-4-1 formation whenever Villa had possession.
This was most of the game – Villa had 78% possession across more than 100 minutes of play – and while it was not pretty, it was certainly effective in frustrating the hosts and neutralising their creative players.
It also frustrated the supporters, who were treated to a light show and fireworks before kick-off as anticipation grew of a move to the top of English football.
But as the nerves grew and the visitors became bolder, what should have been Villa’s big night turned into a damp squib.
Credit must be given to United however, who now have four points from their first three games since Wilder’s return to the club to boost their hopes of Premier League survival – they have moved off the bottom of the table, although they remain five points from safety after Zaniolo’s equaliser.
Bailey denied after Ramsey foul
Instead the story of this game became another tale about refereeing decisions, both overturned and not by VAR.
Villa’s first run in with officials came when Watkins looked to meet Lucas Digne’s looping cross, with Souza appearing to push the forward to the ground before he had a chance to head the ball.
It was not deemed a clear and obvious error by Taylor so the on-pitch decision stood.
They were again denied when Bailey seemed to have put the hosts in front with a clinical finish from Watkins’ low cross, after United full-back George Baldock was dispossessed in his own box.
Although not immediately clear, replays showed Ramsey had held Foderingham’s arm at the set piece.
A bigger let-off for Baldock came shortly after when the ball appeared to hit his forearm in the area, only for Taylor and VAR to say it had come off his chest.