​Paul Merson is backing Arsenal to heap more misery on to Jose Mourinho and Manchester United when the two sides meet on Wednesday evening. 

The Gunners sit eight points ahead of the Red Devils after both sides have had a drastically different start to their season. Arsenal have been impressive under new manager Unai Emery, and are coming off the back of a exceptional 4-2 win over rivals ​Tottenham. 

Arsenal FC v Tottenham Hotspur FC - Premier League

​Manchester United have the shadow of their former selves this year having dropped points to the likes of ​Southampton and ​Crystal Palace in recent weeks. 

Paul Merson, speaking to ​Sky Sports, said: “In the past we’ve seen ​Arsenal go to Old Trafford in form, play well but somehow still end up losing the game.

"However, unless Manchester United really pick their game up or the Gunners hit a brick wall after their efforts against Tottenham, I just can’t see how United win. I really can’t!”

Merson emphasised that he wants Emery to include both ​Pierre-Emerick Aubameyang and ​Alexandre Lacazette in the starting XI, as they both caused problems for Tottenham in Arsenal's derby win.

When asked about United's current form, Merson seemed to suggest that United have lost their mojo. He said "We’ve got to remember this a different Man Utd to the one we used to watch.

“When United got back to 2-2 at Southampton on Saturday there should have been only one winner. However, they just didn’t kick on and it was like they were grateful to be back level at 2-2. 

“It’s the same club but the players are nowhere near in the same calibre. That’s the problem and that’s something we have to keep reminding ourselves. This is not the United of old and if they somehow managed to get in the top four they’d be pulling up trees.”

The Gunners lost 2-1 in this fixture last year, as ​Marouane Fellaini scored a late winner, but Merson is backing Arsenal to reverse the scoreline and win 2-1.