Crystal Palace boss Oliver Glasner has come to the defence of Ruben Amorim's infamous system but highlights the key difference in his side.
The Eagles boss deploys the same formation as Amorim however, Glasner's Palace sit fifth in the Premier League heading into the weekend after an impressive start to their season.
Meanwhile, following a dismal display and result against a 10-man Everton, United have slumped to 10th in the league on a run of three without victory, with Gary Neville among the critics for Amorim's approach.
Palace welcome Amorim's side to Selhurst Park on Sunday, having beaten United on three of the last four occasions. It's a run against United that included a 2-0 win at Old Trafford last season when a Jean-Philippe Mateta brace sunk Amorim's side.
Despite United's poor recent run and a staunch critique of Amorim's formation, Glasner has pointed to the underlying numbers to defend the United boss.
"It's really funny talking about the 3-4-3 system, and I think United have the highest xG in the Premier League for scoring goals," Glasner said.
"Their team has changed. Especially in attack. They needed more goals and they invested £200m, buying three players up front.
"Also, now they have players who can play very intense like [Bryan] Mbeumo.
"For me, it's impressive to see. We compared it [their last meeting] to where they are now. I think their work-rate is much higher than it was last year and then they get the reward."
Palace also rank among the top clubs for expected goals this season, however, Glasner suggests his deployment of the 3-4-3 formation allows his side to defend better, with the Eagles second only to Arsenal with the fewest goals conceded.
"We're playing the same system," Glasner added.
"So it looks like it's a good attacking system. Also, as we show it, you can have a very good defensive structure with it.
"So it's all about what you do with the system and how fluid you are in attack and how creative you are. I'm really looking forward to the game."