Jurgen Klopp watched his side book their place in the quarter-finals of the Europa League after sealing a 3-1 aggregate victory over their bitter local rivals.
Liverpool came from a goal down to earn a 1-1 draw against United at Old Trafford on Thursday night as they took a step closer towards the Europa League final.
The Reds now turn their attentions back to domestic affairs and their trip to the south coast on Sunday afternoon.
However, former Arsenal man Merson is tipping Ronald Koeman’s side to beat the Reds at St Mary’s and dent their hopes of securing a top-four finish this season.
Writing in his column for Sky Sports, Merson said: “Southampton have had some superb results in recent weeks.
“Their form has completely turned around. Liverpool put a lot of effort into their Europa league clash with Manchester United at Old Trafford on Thursday.
“It will certainly take a lot out of them so I’m predicting a 2-1 Southampton win.”
Liverpool are currently eighth in the table and seven points off fourth place.
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