West Ham United were twice pegged back by Barclays Premier League leaders Manchester United on Wednesday night and had to settle for a point from a pulsating Boleyn Ground encounter.
Ricardo Vaz Te's first half header was cancelled out by Antonio Valencia, but the Hammers came roaring back and re-took the lead on 55 minutes thanks to Mohamed Diame's screamer.
West Ham's high-energy game had the runaway leaders rattled at times, but they rediscovered their composure to net a second equaliser through Robin van Persie.
The point represented the east Londoners' third successive draw and extended their unbeaten run to a fourth game as they moved to within a point of tenth-placed Fulham.
West Ham started like a train and were a mere whisker away from taking a fifth minute lead, when Andy Carroll took the ball down on the edge of the box, turned and produced a left-footed shot which whistled just past the near post.
The Hammers were looking brighter in their play and they were rewarded in the 17th minute with the opening goal.
Sir Alex Ferguson's side were undone by the speed of a Hammers break, with Diame driving forwards after Wayne Rooney squandered possession deep in opposition territory.
The Senegal international picked the perfect moment to offload to Matt Jarvis down the left, who carried the ball into the area, ghosted past Rio Ferdinand and stood up an inviting cross for Carroll to knock back towards Vaz Te, who stooped to head home.
It was a goal reminiscent of the type of counter-attacking football shown so regularly by the Red Devils, although they struggled to find that as the Hammers claimed early supremacy.
The champions-elect are well capable of hurting the opposition in a blink of an eye, though, and so they proved with their 31st minute equaliser. Valencia was the man who was given the simple task of tapping home after van Persie made tracks down the left and slipped the ball inside for Shinji Kagawa to skip past Winston Reid and play the ball square.
West Ham were undeterred and began the second period just as they had the first. With 52 minutes on the clock Carroll spied a chance from 30 yards and volleyed just over the top.
Then, three minutes later, Diame bettered that with a goal of the highest quality. Guy Demel gave him possession in the right channel, and after dropping his shoulder to rid himself of Wayne Rooney's attentions, sent a fierce left footed shot curling out of David de Gea's reach and into the bottom corner.
The visitors probed for an instant response and Jussi Jaaskelainen was fortunate that he had Gary O'Neil behind him to clean up after Rooney's shot bobbled over his hands.
With 69 minutes on the clock Jaaskelainen had to show fine reactions to thrust up a hand and divert van Persie's point blank header over the top, but Ferguson's side were pressing and the equaliser was not far away.
That it stood was up for debate as van Persie looked to be in an offside position when Kagawa bent in the shot which clattered off both posts and fell for the Dutchman to knock home.
The flag stayed down and the Hammers were left with 13 minutes to defend their point, but they saw out time to climb yet closer to the top half of the table.
West Ham United: Jaaskelainen; Demel, Collins, Reid, O'Brien; O'Neil (Noble 68); Vaz Te, Diame (Collison 82), Nolan (Taylor 82), Jarvis; Carroll
Subs: Henderson (GK), C.Cole, Maiga, Pogatetz
Goals: Vaz Te 17, Diame 55
Booked: Carroll
Manchester United: De Gea; Rafael, Ferdinand, Vidic, Evra; Jones, Carrick, Kagawa (Hernandez 77); Valencia, van Persie, Rooney (Giggs 71)
Subs: Amos (GK), Evans, Nani, Welbeck, Cleverley
Goals: Valencia 31, van Persie 77
Referee: Lee Probert
Attendance: 34,692