Diop has suggested that he has got even better than last year now, after he impressed during West Ham’s 3-1 victory over United last season.
Jose Mourinho, who was in charge of the Red Devils then, came out and praised Diop publicly after the game.
United are now due to visit West Ham’s stadium for the first time since that occasion on Sunday.
And Diop has suggested that Ole Gunnar Solskjaer’s side can expect an even tougher task getting past him.
“Personally I don't think I played a very good game and when I reviewed it, I saw what I did wrong and this year I am going to try to improve on it,” Diop said.
"I think I am already a better player, I have more experience but I still need to improve and will continue to work towards that.”
Manchester United fans have hit back at the West Ham man though, and suggested that he shouldn’t be putting out any warnings about his ability.
By signing maguire we've already avoided making this mistake— Peter Thomas (@PeterTh06677578) September 20, 2019
If he is up against Rashford he is going to look like prime Ramos but if Martial plays haha good luck— Tameez Abdool Sattar (@TameezSattar) September 20, 2019
He shd just shut up. City put 5 past them on the opening day!— Stunna Perch (@pstunna6) September 20, 2019
u are bang average mate..Mason will tear u apart— Evi14 (@appau_evans) September 20, 2019
You Wil regret this— takaza boss (@LlewellynMarman) September 20, 2019
someone wants a move— jack (@Ginaldum) September 20, 2019
This will be a mistake man, 4-0 loss incoming— @finley_mclellan (@finley_mclellan) September 20, 2019
Diop was actually linked with a move to United over the summer, but West Ham were asking for £75 million for the centre-back, as reported by the Telegraph.
The 22-year-old has enjoyed a strong start to this campaign, where he is playing a key role for Manuel Pellegrini’s side once again.
If West Ham can beat the Red Devils it would take their start from good to excellent, and leave them sat on 11 points after six games.
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