Key Moments
The Red Devils' poor run of form persisted at Leeds' fortress, but manager the Portuguese tactician had Matheus Cunha to thank for the team avoiding even more damage against their old rivals.
The Everton loanee directed a first-half effort against the post for the in-form home team before Brenden Aaronson finished superbly with a low, 62nd-minute shot.
At that stage, Amorim was under intense scrutiny after his side had been held by struggling Wolverhampton Wanderers at Old Trafford earlier in the week.
However, against a team who had less time to prepare, the forward levelled three minutes after the opener when he ran on to a pass from substitute Joshua Zirkzee and guided a shot underneath advancing Leeds goalkeeper Lucas Perri.
It was only the South American's fourth goal since his high-profile summer move and came at a time when the manager is without several key attacking players due to a mix of injury and national team commitments.
Not that you would expect Leeds to sympathise with that given their own tight schedule.
The Swiss attacker forced a diving save out of visiting goalkeeper Senne Lammens with a spectacular overhead kick, and visiting heads were in hands when Benjamin Sesko, who is finding it hard to make an impact, turned his teammate's cut-back wide from close range.
Cunha, who had a goal disallowed for offside much earlier in the contest, also fired against a post late on.
The point prolongs the home side's unbeaten run to seven games, their longest such streak since over two decades ago, and takes them a significant margin clear of the drop zone.
For the Manchester United though, it was yet another chance to move into fourth spot, albeit only for a matter of hours, wasted.
With the Africa Cup of Nations reaching its latter stages, the United coach could be understood for hoping the involved countries make a swift exit.
Current injuries to skipper Bruno Fernandes and England international Mason Mount only exacerbated the impact the unavailability of other attackers is having on the team's squad.
It's not that the absent players are the answer to all of the club's problems. After all, they were part of the side that suffered disappointing results earlier in the campaign.
But without them, the boss has few attacking options.
He evidently does not trust teenager Shea Lacey or the seasoned Zirkzee, even though the Dutch forward delivered the assist for the equaliser almost instantly after his arrival as a substitute.
That leaves the Brazilian, who has now scored a small tally in recent outings, and others playing out of their preferred positions, alongside Sesko.
On this showing, the big-money frontman looks similar to previous struggling signings, lacking in belief and conviction in front of goal.
His failure to turn home the cross means it is now a long run without a goal for the young striker.
After memorable victories in their previous home games, the arrival of their fiercest rivals to Elland Road was a bit drab affair.
True, there were instances of expected atmosphere, but the hostile edge was not as pronounced as in other fixtures.
The home fans were more concerned about their side's inability to get sustained possession in advanced areas for any length of time.
The striker's header that clipped the post was an isolated moment of threat in a congested first half.
It still felt as though Leeds were struggling when a mistake opened the door for Aaronson.
For a short moment, Leeds' ecstatic fans thought they were about to secure a coveted win against their old foes.
Nevertheless, there is a wider context for the manager and Leeds to deal with.
When they endured a poor run of form earlier in the campaign, many speculated about the manager's future.
In contrast, he is now masterminding significant progress.
The task is not completed yet but gradually, the team are getting nearer to achieving their survival.
Leeds have a Premier League trip to St James' Park in midweek, followed by the start of their FA Cup campaign next weekend. The Red Devils face a league trip to Burnley before also entering their FA Cup journey with a Old Trafford tie.
A passionate film critic with over a decade of experience, specializing in indie and international cinema.