In the summer of 2019, United splashed out £50 million to bring in the right-back, who became the sixth-most expensive defender ever at the time.
Wan-Bissaka had just come off a strong season with Palace and won their Player of the Year award.
But Arsenal legend Merson expressed concern over the signing and was unsure about Wan-Bissaka being good enough on the ball and going forward for United.
And while he has the nickname 'the Spider' for his slide-tackling abilities, Merson claimed that the regularity of which he goes to ground was telling.
📽 Back in 2019 Paul Merson wasn’t sure about Manchester United signing Aaron Wan-Bissaka from Crystal Palace for £50m.💰— Football Daily (@footballdaily) August 11, 2022
He called it first! 👀 pic.twitter.com/x5s6xeZGjx
"I like him, my worry is - whenever we show clips of him he's always slide-tackling," Merson said on Sky Sports' Soccer Saturday after a long pause.
"Now that tells me you're out of position and you're moving up another level. He's not the greatest going forward, now you're playing for Man United, who are going to have 70 per cent of the ball when they play games. He's got to get forward.
"I think it's going to take him time. It's a massive jump, this. I just think whenever I see him he's always slide-tackling, players are going to suss this out and they're going to start stopping the ball and cutting it back or chipping it over his foot.
"I worry for United, I don't see any good business."
Merson was also critical of United's decision to make Harry Maguire the most expensive defender of all time following an £80 million switch, branding the fee "ridiculous" in a two-minute rant.
Wan-Bissaka impressed in his early days at Old Trafford but Merson's prediction has come true and after being unfancied by interim boss Ralf Rangnick, he now looks to be second-choice behind Diogo Dalot under new manager Erik ten Hag.
There has been talk of a loan move back to Palace being on the cards in a bid to get Wan-Bissaka some valuable game-time in an environment he knows very well.
Featured Image Credit: Image: Sky Sports & Alamy
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