Manchester United have been held 1-1 by West Ham United to make it four league draws in succession at Old Trafford for the first time in 36 years.
The Red Devils recovered from an early setback but could not add a second goal despite their numerous openings, meaning that they are 11 points off the summit following a run of two top-flight wins in 10.
West Ham are now unbeaten against their opponents in their last three meetings at this former fortress, meanwhile, although they may well have snatched just a third victory here in 24 attempts had they taken a couple of late chances of their own.
The Hammers were ahead inside just 90 seconds, scoring the second-fastest goal for a visiting side at Old Trafford in Premier League history thanks to Diafra Sakho's bullet header.
Dimitri Payet floated in a free kick, given away needlessly by Jesse Lingard, and Sakho got ahead of marker Zlatan Ibrahimovic to open his scoring account in what has been an injury-hit campaign thus far.
The hosts were putting together some patient passing moves, one of which ended with Juan Mata firing in his side's first shot which was right down the throat of Darren Randolph 15 minutes in.
It was another patient piece of play which led to the equaliser, as Paul Pogba lifted the ball over the opposition defence and Ibrahimovic simply glanced past Randolph to round off a 22-pass move.
Despite seeing his side wrestle back control of the game and draw level, Jose Mourinho was unhappy with referee Jonathan Moss's decision to show Pogba a yellow - ruling him out of the rematch between these two teams in the EFL Cup here next Wednesday - and kicked a water bottle on the sidelines.
Moss inevitably sent the Portuguese to the stands, the second time he has done so in the space of 12 months, with assistant Rui Faria instead taking over for the remainder.
From that point on the Red Devils looked the only team likely to score a potentially decisive second in the remainder of the first half - Lingard flicking the ball over the bar from close range and Ibrahimovic glancing wide at the back post.
Lingard was also denied by Randolph, again preferred to Adrian in goal this afternoon, late in the half, while Angelo Ogbonna threw his body on the line to block a goalbound strike from Ibrahimovic.
Man United's best chance fell the way of Marcus Rashford, though, who was slotted clean through on goal only to be thwarted by an inspired Randolph.
West Ham were again the quicker out of the blocks in a sloppy start to the second half, with Sakho looping a corner over the bar in what was the visitors' best opening since making the early breakthrough.
The Irons continued to dictate the tempo of things for the next 15 minutes of the half, coming close through a cheeky Payet attempt which almost caught David de Gea out, though the Spaniard was well positioned to punch the ball over the bar.
It was not until Wayne Rooney and Henrikh Mkhitaryan were introduced in the final third of the match that the hosts finally started to show signs of moving back out of first gear, as Rooney turned Ibrahimovic's first-time pass into the arms of Randolph with his first touch.
With time fast ticking down, Mkhitaryan's shot was blocked by a visiting player inside the box but only as far as Lingard on the edge of the box, who rifled one down the middle where Randolph was again in the right place to routinely keep it out.
Mkhitaryan, with just the two starts in all competitions since joining the Red Devils in the summer, then struck the post and Lingard followed up to tap it into an empty net, but the offside flag was quickly up.
Pogba was next to try his luck from 20 yards, failing to get the beating of Randolph, and there was a sense of inevitably about the final scoreline when the Irishman again got in the way to prevent Ibrahimovic from finding a way through at the back post.
West Ham have conceded their fair share of late goals this term, and there was almost another to add to the list when Ibrahimovic nodded the ball over Randolph and looked set to roll over the line, only for Cheikhou Kouyate to read the danger and clear before he could do so.
Ashley Fletcher, who left Man United in the summer following seven years in their age-grade sides, had a chance late on to seal three points at the home of his former club, only to fire straight at De Gea after weaving through a sea of bodies.
The Hammers had never scored more than one goal in a single game here in 20 Premier League attempts, though, so holding on and taking a point was always likely to be their priority, which they managed to do despite some late pressure.