Liverpool will put their 18-game unbeaten run in the Premier League on the line at Old Trafford on Sunday.

While that streak contains a 4-2 win at the home of Manchester United, triumphs at the Red Devils' ground have been frustratingly rare over the years.

It was only the Reds’ second victory in their last 16 matches in all competitions there, and they have only returned from United with three points 17 times in top flight history.

Even though Liverpool have the better recent form of the two teams, it will not be easy for them to win this weekend. However, one of their strengths combined with their two players who are due a goal align nicely with a definite area of United weakness.

2020/21 was one of the strangest Liverpool seasons any of us can remember for a whole host of reasons, and one way in which it was unusual related to the club’s record with set piece goals.

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Jurgen Klopp’s side scored eight goals from dead ball situations in their opening 23 matches – not a red-hot return but one every three games isn’t bad – only to then play 26 consecutive games without scoring from a set play.

In that period, they had an almost unbelievable 91 set piece shots without once beating an opposition goalkeeper.

Their drought ended at Old Trafford in May, and in quite some style. Trailing to Bruno Fernandes’ early goal, Diogo Jota equalised following a corner and Roberto Firmino then gave Liverpool the lead in first half stoppage time when he headed in Trent Alexander-Arnold’s free-kick delivery.

The cork was out of the bottle and the set play goals have flowed out of Liverpool ever since. The Reds scored four times in their remaining three games of the campaign, with Alisson Becker’s header the highlight, and have added another eight in all competitions in 2021/22.

This potency from set pieces isn’t simply going to be a problem for United thanks to Raphael Varane being injured and Harry Maguire looking out of sorts last weekend either.

Since the start of 2018/19, the season in which Ole Gunnar Solskjaer was appointed, the Red Devils have conceded 40 Premier League goals from set plays, a total only Everton, with 41, can top. Of the 15 clubs who have been in the top flight consistently in this period, only Crystal Palace have a worse goal difference in terms of set pieces.

United may have only conceded three times from dead ball situations in 2021/22, but they have already proved costly. Kortney Hause scored a winner for Aston Villa from a corner at Old Trafford last month, while two of the goals in their 4-2 defeat at Leicester were from set plays too.

This knowledge should have Liverpool’s analysts licking their lips in anticipation, as it offers the Reds a definite weakness to exploit, particularly as the side are due a certain type of set piece goal for a couple of reasons.

Klopp’s team may have scored eight set piece goals this term but not one has been directly set up from the initial corner or free-kick. The only two to be assisted at all have come from one player getting to the initial delivery and guiding the ball to a teammate: Virgil van Dijk to Mohamed Salah against Crystal Palace, then Divock Origi to Takumi Minamino in the League Cup game at Norwich.

And though van Dijk will have enjoyed picking up the sixth assist of his Liverpool career, he will know that his primary aim in the opposition box is to score goals from set pieces, and the same is true of Joel Matip.

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Brighton’s Shane Duffy has had the most set play shots in the Premier League this season with 14 (per WhoScored) but then come Matip and van Dijk on 10 apiece. The Liverpool pair are also among the 10 players in the division to have amassed at least one expected goal’s worth of chances without yet finding the back of the net (per FBRef).

It’s feasible that all these factors could collide perfectly at Old Trafford. United don’t defend set plays well, Liverpool have created the joint-most chances in the top flight this season from corners and free-kicks combined without a direct assist, and they have two centre-backs who are both due to score soon.

When everybody will be expecting more Mo magic in Manchester, it may be a less glamorous style of goal which wins the points on Sunday.