Match Summary
Manchester United's poor recent struggles continued at Elland Road, but manager Ruben Amorim had his Brazilian forward to thank for the team avoiding even more disappointment against their old rivals.
The Everton loanee directed a first-period attempt against the post for the in-form hosts before the American midfielder finished superbly with a low, 62nd-minute effort.
With the goal, Amorim was under intense scrutiny after his side had been held by bottom-of-the-table Wolves at Old Trafford earlier in the week.
However, against a team who had two days less to recover, Cunha restored parity three minutes later when he latched onto a pass from substitute the Dutchman and slid a shot underneath rushing Leeds 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 four key attacking players due to a combination of fitness issues and national team commitments.
Not that you would expect the hosts to sympathise with that given their own tight schedule.
Noah Okafor forced a diving save out of Manchester United goalkeeper Senne Lammens with a spectacular 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 six yards out.
The goalscorer, who had a goal ruled out for offside much earlier in the match, also fired against a post late on.
The draw extends Leeds' unbeaten run to seven games, their best such streak since over two decades ago, 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 Africa Cup of Nations reaching its knockout phase, the United coach could be forgiven for hoping the involved countries make a pretty quick exit.
Current injuries to captain Bruno Fernandes and England international Mason Mount only heightened the impact the unavailability of other forwards is having on Amorim'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 poor results earlier in the season.
But without them, Amorim has limited alternatives in attack.
He clearly does not have full faith in teenager Shea Lacey or the seasoned Zirkzee, even though the Netherlands forward delivered the assist for Cunha's equaliser almost instantly after his arrival as a substitute.
That leaves the Brazilian, who has now scored a small tally in five games, and others operating out of their natural positions, alongside Sesko.
On this evidence, the expensive frontman looks no better than previous struggling signings, lacking in belief and assurance 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 fiercest rivals to home was a bit drab affair.
True, there were moments of expected fervor, but the hostile edge was not as pronounced as in previous encounters.
The home fans were more concerned about their side's inability to get worthwhile possession in dangerous areas for any length of time.
The striker's header that struck the post was an isolated moment of quality in a congested first half.
It still felt as though the hosts were struggling when a defensive error opened the door for the opener.
For a short moment, The home 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 the club to deal with.
When they endured a difficult run of form earlier in the campaign, many speculated about the manager's position.
In contrast, he is now masterminding clear improvement.
The job is not done yet but gradually, Leeds are getting nearer to securing their top-flight status.
Leeds 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 Premier League trip to Burnley before also entering their cup journey with a home tie.
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