Key Moments
The Red Devils' poor run of form continued at Leeds' fortress, but manager the Portuguese tactician had Matheus Cunha to thank for the team not suffering even more disappointment against their old rivals.
The Everton loanee headed a first-half attempt against the post for the in-form hosts before the American midfielder finished superbly with a driven, 62nd-minute shot.
With the goal, the United boss was under intense scrutiny after his side had failed to beat bottom-of-the-table Wolves at home earlier in the week.
However, against a team who had two days less to recover, the forward levelled three minutes later when he latched onto a through ball from substitute Joshua Zirkzee and slid a shot underneath rushing Leeds goalkeeper Lucas Perri.
It was only the South American's fourth Premier League goal since his high-profile summer move and came at a time when Amorim is without four key attacking players due to a mix of fitness issues 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 the Slovenian striker, who is finding it hard to make an impression, turned his teammate's cut-back wide from close range.
The goalscorer, who had a goal disallowed for offside much earlier in the contest, also fired against a post in the dying moments.
The draw extends Leeds' unbeaten run to seven games, their best such streak since 2001, and takes them a significant margin clear of the drop zone.
For the visitors though, it was yet another opportunity to move into fourth spot, albeit only for a matter of hours, squandered.
With the AFCON reaching its latter stages, the United coach could be understood for hoping the participating nations make a swift exit.
Existing injuries to skipper Bruno Fernandes and Three Lions star Mason Mount only heightened the impact the unavailability of other attackers is having on Amorim's options.
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 experienced poor results earlier in the season.
But without them, the boss has limited attacking options.
He evidently does not trust youngster Shea Lacey or the seasoned Zirkzee, even though the Dutch forward delivered the assist for the equaliser almost immediately after his arrival as a replacement.
That leaves the Brazilian, who has now scored a small tally in recent outings, and others operating out of their preferred positions, alongside Benjamin Sesko.
On this showing, the expensive frontman looks no better than previous underwhelming signings, lacking in confidence and conviction in front of goal.
Sesko's failure to turn home the cross means it is now a long run without a goal for the new signing.
After memorable victories in their previous home games, the arrival of their biggest rivals to Elland Road was a bit drab affair.
True, there were moments of typical fervor, but the intimidating edge was not as evident as in previous encounters.
The home fans were more concerned about their side's struggle to get sustained possession in advanced areas for any length of time.
The Calvert-Lewin header that clipped the post was an rare moment of quality in a congested first half.
It still felt as though the hosts were struggling when a mistake opened the door for the opener.
Ever so briefly, The home delirious 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 suffered a difficult run of form earlier in the campaign, many speculated about the manager's position.
In contrast, he is now overseeing significant improvement.
The task is not completed yet but gradually, Leeds are getting nearer to securing their survival.
The Yorkshire club have a top-flight trip to St James' Park in midweek, followed by the start of their domestic cup campaign next weekend. Manchester United face a Premier League trip to Burnley before also beginning their cup journey with a home tie.