Tactical Watch: The ultimate test for Saints' left side

This weekend Southampton travel up to Anfield to face Liverpool.

To suggest that’s a difficult trip to make would be an understatement. In January this year, Burnley became the first opposing team to win there in 69 attempts (thanks in part to a wretched injury crisis), and with players back fit and healthy, they’re now 14 games into a fresh streak.

They’re playing to a formidable level, just four points off pace-setters Chelsea at the top, and with Mohamed Salah (11) in top-scoring form. Having watched their 4-0 demolition of Arsenal last Saturday, Ralph Hasenhüttl will know Saturday presents about as stern a challenge as the Premier League offers.

The identity of Liverpool’s major threats are no secret: Salah cutting in off the right and shooting; Sadio Mané crashing into the box from the left; Diogo Jota drifting across the front line to find space; Andy Robertson steaming forward on the left; and Trent Alexander-Arnold swinging in deliveries from the right.

The dynamic of their attack, though – the way it tactically functions – has altered a little this season. It’s more biased towards the right than ever before, and features a clever rotation to help create space.

Liverpool’s formation looks a clear-cut 4-3-3 featuring two No. 8s in midfield – until the right-sided No. 8 suddenly shoots wide and overlaps Salah on the flank. Salah then moves in towards the box, while Alexander-Arnold steps inside to the spot the No. 8 vacated.

This does two things: 1) gets the Premier League’s top goalscorer into the box and into shooting positions frequently, and 2) gets Alexander-Arnold into a position he can cross from while being difficult to close down. The midfielder, which has been any of Harvey Elliott, Naby Keïta, Jordan Henderson or Alex Oxlade-Chamberlain, ends up wide after dragging a marker away and helping create these spaces.

Trent’s six Premier League assists and expected assists (xA) tally of 4.9 are second only to Salah in the league this season. Either from open play or set-pieces, he’s creating good chances at a high volume, unleashed by this new rotation Klopp has introduced to his team.

While far from the only threat they pose, Salah and Trent are the two most pivotal attacking players and the team tactics are skewed toward getting them into positive positions.

Mané and Jota have then been able to interpret these movements and profit off them, while a ferocious pressing game and the imperious Fabinho has wrestled several sides into submission, trapping them in their own half for longer periods.

In order to withstand it, extreme defensive work rate (and perhaps an extra player) is needed from the left side to block up the space Liverpool try to create. West Ham’s close-knit defensive lines and use of workhorse winger Pablo Fornals earlier this month did a good job of at least keeping Salah a little quieter. Ibrahima Diallo and Moussa Djenepo are two different options that could achieve a similar plan for Saints.

Elsewhere, strong runners up top, such as Ché Adams, are crucial to relieve pressure and challenge for balls in the channels, while concentration is the name of the game for the defence, as so many of Liverpool’s attackers swarm and move.