Key Moments
The Red Devils' disappointing recent struggles persisted at Leeds' fortress, but head coach Ruben Amorim had his Brazilian forward to thank for the team not suffering even more damage against their old rivals.
The Everton loanee directed a first-period effort against the post for the confident home team before Brenden Aaronson finished superbly with a driven, 62nd-minute effort.
At that stage, Amorim was in the firing line 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 levelled three minutes later when he latched onto a pass from introduced the Dutchman and guided a finish underneath rushing home goalkeeper Lucas Perri.
It was only the Brazilian's fourth goal since his high-profile summer move and came at a time when the manager is without four 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 lack of preparation time.
The Swiss attacker forced a full length save out of visiting goalkeeper Senne Lammens with a audacious overhead kick, and visiting heads were in hands when Benjamin Sesko, who is struggling to make an impression, turned Zirkzee's cut-back wide from six yards out.
The goalscorer, who had a goal ruled out for offside much earlier in the contest, also fired against a post in the dying moments.
The draw prolongs Leeds' unbeaten run to seven matches, their longest such streak since 2001, and takes them a significant margin 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 matter of hours, wasted.
With the AFCON reaching its knockout phase, Amorim 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 exacerbated the impact the unavailability of other forwards is having on Amorim'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 clearly does not trust youngster Shea Lacey or the much more experienced Zirkzee, even though the Netherlands forward provided the through ball for the equaliser almost instantly after his arrival as a replacement.
That leaves the Brazilian, who has now scored three goals in five games, and others playing out of their natural positions, alongside Sesko.
On this evidence, the big-money frontman looks no better than previous struggling signings, lacking in confidence and assurance in front of goal.
Sesko's failure to turn home the cross means it is now nine games without a goal for the young striker.
After memorable victories in their previous home games, the arrival of their biggest rivals to Elland Road was a comparatively subdued affair.
True, there were moments of expected fervor, but the intimidating edge was not as evident as in previous fixtures.
The home fans were more preoccupied about their side's struggle to get worthwhile possession in advanced areas for any prolonged period.
The striker's header that clipped the post was an rare moment of threat in a tight 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 rare win against their old foes.
Nevertheless, there is a much bigger picture for the manager and the club to deal with.
When they suffered a difficult run of form earlier in the season, many thought about the manager's position.
In contrast, he is now overseeing clear improvement.
The job is not completed yet but step by step, the team 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. The Red Devils face a Premier League trip to Turf Moor before also entering their FA Cup journey with a home tie.
Marcus Thorne is a seasoned esports analyst and community manager with over a decade of experience in competitive gaming ecosystems.