Match Summary
The Red Devils' poor run of form persisted at Elland Road, but head coach the Portuguese tactician had Matheus Cunha to thank for the team avoiding even more damage against Leeds.
The Everton loanee headed a first-half attempt against the woodwork for the in-form hosts before the American midfielder applied a cool finish with a low, 62nd-minute shot.
At that stage, the United boss was under intense scrutiny after his side had been held by bottom-of-the-table Wolverhampton Wanderers at home earlier in the week.
However, against a team who had two days less to prepare, the forward levelled three minutes after the opener when he ran on to a through ball from substitute the Dutchman and slid a finish underneath advancing home goalkeeper Lucas Perri.
It was only the South American's fourth Premier League goal since his big-money 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.
Noah Okafor 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 finding it hard to make an impact, turned Zirkzee's cut-back wide from close range.
The goalscorer, who had a goal ruled out for offside much earlier in the contest, also fired against a post late on.
The draw extends Leeds' unbeaten run to seven games, their best such streak since 2001, and takes them a significant margin clear of the relegation zone.
For the Manchester United 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, Amorim could be understood for hoping the involved countries make a swift exit.
Existing injuries to captain Bruno Fernandes and Three Lions star Mason Mount only exacerbated the impact the unavailability of other attackers is having on Amorim's options.
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 experienced disappointing results earlier in the season.
But without them, the boss has limited attacking options.
He clearly does not trust youngster Shea Lacey or the seasoned Zirkzee, even though the Netherlands forward provided the through ball for Cunha's equaliser almost instantly after his arrival as a substitute.
That leaves Cunha, who has now scored three goals in five games, and others operating out of their preferred positions, alongside Sesko.
On this showing, the expensive frontman looks no better than previous underwhelming 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 previous home games, the arrival of their biggest rivals to home was a bit drab affair.
True, there were instances of expected atmosphere, but the intimidating edge was not as evident as in previous fixtures.
The home fans were more preoccupied about their side's inability to get sustained possession in dangerous areas for any prolonged period.
The Calvert-Lewin header that struck the post was an rare 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 the opener.
For a short moment, Leeds' delirious 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 suffered a poor run of form earlier in the season, many thought about the manager's future.
Instead, he is now masterminding significant improvement.
The job is not done yet but gradually, the team are getting nearer to securing their survival.
The Yorkshire club have a top-flight trip to Newcastle in midweek, followed by the start of their FA Cup campaign next weekend. The Red Devils face a league trip to Burnley before also beginning their cup journey with a home tie.
Marcus Sterling is a financial analyst specializing in precious metals, with over 15 years of experience in global markets and investment strategies.