Match Summary
The Red Devils' poor recent struggles continued at Leeds' fortress, but head coach Ruben Amorim had Matheus Cunha to thank for the team not suffering even more disappointment against their old rivals.
The Everton loanee directed a first-half attempt against the post for the confident home team before the American midfielder finished superbly with a low, 62nd-minute shot.
With the goal, Amorim was under intense scrutiny after his side had been held by struggling Wolverhampton Wanderers at home earlier in the week.
Nevertheless, against opponents who had less time to prepare, Cunha restored parity three minutes after the opener when he ran on to a through ball from substitute Joshua Zirkzee and guided a shot underneath advancing Leeds goalkeeper Lucas Perri.
It was only the Brazilian's fourth Premier League 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 international duty.
Not that you would expect Leeds to care about that given their own lack of preparation time.
The Swiss attacker forced a full length save out of Manchester United 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 impact, turned Zirkzee's cut-back wide from six yards out.
The goalscorer, who had a goal disallowed for offside much earlier in the contest, also blasted against a post late on.
The draw extends Leeds' unbeaten run to seven games, their longest such streak since over two decades ago, and takes them eight points clear of the drop zone.
For the Manchester United though, it was yet another opportunity to move into the Champions League places, albeit only for a short time, squandered.
With the AFCON reaching its knockout phase, Amorim could be understood for hoping the participating nations make a pretty quick exit.
Existing injuries to captain Bruno Fernandes and England international Mason Mount only heightened the impact the unavailability of other attackers is having on Amorim's squad.
It's not that the missing pair 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 season.
But without them, the boss has limited attacking options.
He clearly does not trust teenager Shea Lacey or the much more experienced Joshua Zirkzee, even though the Netherlands forward provided the through ball for the equaliser almost immediately after his arrival as a substitute.
That leaves Cunha, who has now scored three goals in recent outings, and others playing out of their preferred positions, alongside Benjamin Sesko.
On this showing, the big-money frontman looks similar to previous underwhelming signings, lacking in belief and conviction in front of goal.
Sesko's failure to turn home Zirkzee's cross means it is now a long run without a goal for the new signing.
After memorable victories in their last few home games, the arrival of their fiercest rivals to Elland Road was a bit drab affair.
True, there were instances of typical fervor, but the intimidating edge was not as pronounced as in other encounters.
The home fans were more concerned about their side's struggle to get sustained possession in dangerous areas for any prolonged period.
The Calvert-Lewin header that clipped the post was an isolated moment of threat in a congested first half.
It still felt as though Leeds were finding it tough when a defensive error opened the door for Aaronson.
Ever so briefly, Leeds' delirious fans thought they were about to secure a coveted win against their old foes.
However, there is a wider context for the manager and Leeds to deal with.
When they suffered a poor run of form earlier in the season, many thought about the manager's position.
Instead, he is now masterminding significant progress.
The task is not completed yet but step by step, the team are getting closer to securing their top-flight status.
The Yorkshire club have a Premier League trip to St James' Park in midweek, followed by the start of their domestic cup campaign next weekend. The Red Devils face a league trip to Turf Moor before also beginning their FA Cup journey with a Old Trafford tie.
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