The Red Devils head into the game looking to return to winning ways after the disappointment of back to back draws against Burnley and Leicester City.
Those results have allowed Manchester City to open up a staggering 15-point lead at the top of the table, with Pep Guardiola’s men having only dropped points once this season in the Premier League.
Manchester United are currently second in the table but will want to win Saturday’s game to keep their lead over third placed Chelsea, who head into this weekend’s round of games just a point behind the Red Devils.
And former Arsenal star Merson is fully expecting the Red Devils to claim all three points by beating Southampton at Old Trafford this weekend.
Writing in his column for Sky Sports, Merson said: “Southampton were atrocious at Spurs, and Man Utd weren’t great either against Burnley.
“Man Utd should be blowing teams away, and I still think it will happen at some point.
“Saints are all over the place, and I didn’t see too many of their players playing for Mauricio Pellegrino at Wembley, which is very worrying.
“There are ways of losing football matches, and the way they lost against Spurs was not good at all. I’d be worried coming into this game. If they are battered again, I think Pellegrino could go.
“For Man United, I cannot remember in 90 minutes Romelu Lukaku having a chance against Burnley, and that’s with the vast majority of the ball and being in Burnley’s half for the entire second period.
“I think that’s a problem with both Lukaku and the creativity of the side. But if they can’t blow these away, there will be some unrest at Old Trafford.”
Manchester United look definitely set to build on their sixth-placed finish in the Premier League last season, with the Red Devils currently second in the table.
Jose Mourinho will be hoping to steer his side to Champions League glory, with the Red Devils set to take on Sevilla in the last 16 next year.
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