Both sides would have expected to enjoy a more successful season thus far, yet three points on Sunday could serve as a catalyst for the two teams.
Whilst a victory would enhance United's hopes of securing Champions League football for next season, Leeds currently sit 15th in the table and could potentially move nine points clear of the relegation zone with a win.
Raphael Varane and Edinson Cavani were back in training on Thursday, after the Frenchman missed Tuesday's win against Brighton despite initially being named in Ralf Rangnick's starting XI to take on Graham Potter's side.
Cavani missed the win over The Seagulls as well as Saturday's 1-1 draw at home to Southampton, with the 35-year-old suffering from a groin problem.
Nemanja Matic wasn't involved in training, with the Serbian having been ruled out in recent weeks with a shin complaint.
As for the visitors, Patrick Bamford remains sidelined after not playing since December.
Leeds United: Meslier, Strujik, Koch, Llorente, Dallas, Klich, Ayling, Harrison, Rodrigo, Raphinha, James
Manchester United: De Gea, Shaw, Maguire, Varane, Dalot, McTominay, Pogba, Fernandes, Sancho, Elanga, Ronaldo
One to watch:
Our one to watch for Sunday's fixture is former Manchester United player, and current Leeds attacker, Daniel James.
During his time at Old Trafford, the Welshman divided opinion – many thinking he didn't have the end product to warrant a place in the United squad, whilst others appreciated his commanding work ethic.
But it was no secret that Leeds had been keen on James all along, with the winger almost joining Bielsa's side six months before his move to Manchester.
James originally arrived at Old Trafford for £15 million, and The Red Devils made between £12-15 million profit from his departure.
And although the signing didn't always perform to perfection, he was definitely influential in a United side that vastly improved for a couple of campaigns under then manager Ole Gunnar Solskjaer.
A large portion of fans were sad to see James leave the club, but his never-say-die attitude and constant hard work merited a career in which he would be playing first-team football on a regular basis.
And that is exactly what he has been given so far during his time at Leeds.
The youngster didn't get off to the greatest start after his summer move to Yorkshire, but James has now scored three goals in his last five games whilst playing as a striker in Patrick Bamford's absence.
It will be fascinating to see whether he continues this rich vein of form against his former employers, or whether his ex-teammates will be able to thwart his threats having played alongside him for just over two years.
Head to head:
The two sides have faced each other on a total of 110 occasions, with the hosts winning 26 of those games, United being victorious 48 times, and 36 matches ending in a draw.
In the time since, The Red Devils have won three and drawn one of the four fixtures played in Yorkshire, but Leeds did pull of a shock 1-0 win at Old Trafford in 2010 in the FA Cup thanks to a Jermaine Beckford strike.
Sunday's reverse fixture fell on the opening day of the 2021/22 campaign, with Manchester United running out 5-1 victors.
Leeds United 2 - 2 Manchester United
How to watch:
The 14:00 BST game will be broadcast live on Sky Sports Premier League from 13:00 BST.
Fans can also tune in via the Sky Go app on mobile or tablet devices.