Match Summary
The Red Devils' disappointing recent struggles continued at Leeds' fortress, but head coach the Portuguese tactician had Matheus Cunha to thank for his side not suffering even more damage against their old rivals.
The Everton loanee directed a first-period effort against the woodwork for the confident hosts before the American midfielder applied a cool finish with a low, 62nd-minute shot.
At that stage, Amorim was under intense scrutiny after his side had failed to beat bottom-of-the-table Wolverhampton Wanderers at Old Trafford earlier in the week.
Nevertheless, against a team who had less time to recover, Cunha restored parity three minutes later when he latched onto a pass from introduced the Dutchman and guided a finish underneath rushing 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 Amorim is without four key attacking players due to a mix of fitness issues and national team commitments.
Not that the hosts to care about that given their own lack of preparation time.
The Swiss attacker forced a full length save out of visiting goalkeeper Senne Lammens with a audacious overhead kick, and United heads were in hands when the Slovenian striker, who is struggling to make an impression, turned his teammate's cut-back wide from close range.
Cunha, who had a goal disallowed for offside much earlier in the match, also fired against a post late on.
The draw extends the home side's unbeaten run to seven games, their best such streak since over two decades ago, and takes them eight points clear of the relegation zone.
For the Manchester United though, it was yet another opportunity to move into fourth spot, albeit only for a short time, squandered.
With the AFCON reaching its knockout phase, Amorim could be forgiven for hoping the participating nations make a swift exit.
Existing injuries to skipper Bruno Fernandes and Three Lions star Mason Mount only exacerbated the impact the unavailability of other forwards is having on the team's squad.
It's not that the absent players are the solution to all of the club's problems. After all, they were part of the side that suffered disappointing results earlier in the season.
But without them, the boss has limited alternatives in attack.
He clearly does not have full faith in teenager Shea Lacey or the much more experienced Joshua Zirkzee, even though the Dutch forward provided the assist for Cunha's equaliser almost instantly after his introduction as a substitute.
That leaves the Brazilian, who has now scored three goals in five games, and others operating out of their natural positions, alongside Sesko.
On this evidence, 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 thrilling victories in their last few home games, the arrival of their biggest rivals to home was a bit drab affair.
True, there were instances of typical fervor, but the hostile edge was not as evident as in previous encounters.
Leeds' 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 quality in a congested first half.
It still felt as though the hosts were finding it tough when a defensive error opened the door for Aaronson.
Ever so briefly, Leeds' ecstatic fans thought they were about to secure a coveted win against their old foes.
However, there is a much bigger picture for the manager and Leeds to deal with.
When they endured a poor run of form earlier in the season, many thought about the manager's future.
Instead, he is now masterminding clear improvement.
The job is not done yet but step by step, the team are getting nearer to achieving their survival.
The Yorkshire club have a top-flight trip to Newcastle in midweek, followed by the start of their domestic cup campaign next weekend. The Red Devils face a Premier League trip to Turf Moor before also beginning their FA Cup journey with a home tie.
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