As United bowed out of the Europa League to Liverpool on Thursday night, Louis van Gaal's substitutions again came under the spotlight.
Philippe Coutinho's goal just before half-time meant United had to win 4-1 on the night to get through.
Van Gaal said he was confident his team could do that if required but in the second half he brought on Antonio Valencia, Matteo Darmian and Bastian Schweinsteiger and left Memphis on the bench.
It's not the first time his subs haven't made sense.
Adnan Januzaj (v Sunderland), August 2014
With United chasing a winner at the Stadium of Light in his second game in charge, he swapped holding midfielder Darren Fletcher for Adnan Januzaj.
But instead of pushing Januzaj forward to get a goal - at a ground where he scored twice the season before - he was deployed as a holding midfielder alongside Tom Cleverley.
United created next to nothing and had to settle for a 1-1 draw against a side who would go on to struggle.
Marouane Fellaini (v CSKA Moscow), November 2015
With United again looking for a goal, this time in Europa against CSKA, Van Gaal replaced Anthony Martial with Fellaini in a change that was greeted with boos from the Old Trafford faithful.
Ultimately, Van Gaal got away with it as Michael Carrick, Jesse Lingard and Wayne Rooney combined to find a late goal in a 1-0 win.
Nick Powell (v Wolfsburg), December 2015
United needed to win in Germany to be sure of keeping their Champions League campaign alive.
It was a surprise when Van Gaal named Nick Powell on the bench with the midfielder only just back from a year out.
It was an even bigger surprise when he was thrown in place of Juan Mata after 69 minutes.
With Wolfsburg leading 2-1 and United needing to score twice, Van Gaal left Ashley Young and Andreas Pereira on the bench in favour of Powell.
He had very little impact, United eventually lost 3-2 to go out and a month later Powell was on loan at Hull.
Timothy Fosu-Mensah (v West Brom), March 2015
United were a goal and a man down at the Hawthorns with 10 minutes to go but instead of turning to attacking options Marouane Fellaini and James Weir, Van Gaal decided to change his right-back.
Timothy Fosu-Mensah came on for Matteo Darmian while Fellaini and Weir spent the rest of the match on the bench.
United barely created anything as West Brom held on comfortably.
Marcos Rojo (v Watford), November 2015.
Another one that Van Gaal got away with but it very nearly cost us the game.
Ander Herrera got injured midway through the first half with United dominant, but Van Gaal's decision to put on Rojo, instead of the attack minded Pereira, upset United's equilibrium as Watford staged a second half fightback.
Van Gaal switched to his ill-fated 3-5-2 and needed a late Troy Deeney own goal to snatch the win.