On Friday evening, Southampton faced Liverpool in an intense battle on game day 33 in the Premier League. Thanks to two goals late in the second half, Liverpool were able to win this game with 3-1, maintaining the top spot in the league. Manchester City have played one game less though, trailing by only two points, so the title race continues to stay close. Southampton, on the other hand, remain five points clear of the last relegation spot, which is occupied by Cardiff. This tactical analysis will explain the reasons for this important win for Liverpool and why everyone was once again reaching for their bookie apps to update their bets on who will win the title.
Line-Ups

Home side Southampton played with a 3-4-2-1 formation, which could also be interpreted as a 5-4-1 formation, as we will show later on. This system has worked well for Ralph Hasenhüttl in the last few weeks, especially when they won 2-1 against Tottenham before the international break.
Liverpool also wanted to stick to what has worked well for them throughout the season, so Jürgen Klopp once again used the 4-3-3 formation with Sadio Mané, Roberto Firmino and Mohamed Salah up-front. There were also games with a 4-2-3-1 formation in this season, where Salah would be the striker with Firmino behind him and Mané and Naby Keita or Xherdan Shaqiri on the wings. In this game though, Keita was alongside Georginio Wijnaldum as central midfielder.
Liverpool with a lot of possession
From a tactical standpoint, the plan for both teams was clear from the first minute of the game. Liverpool were forced to create, while Southampton took a reactive approach. It is thus no surprise that Liverpool had a lot more possession (67% to 33%) and played more than twice as many passes (565 to 272). Therefore, Liverpool had to come up with a good plan in order to find a solution against Southampton’s massive defensive block.

It was obvious that Liverpool’s full-backs Andy Robertson and Trent Alexander-Arnold had different tasks. Most of the time, like in this image, they positioned at different heights. While Robertson moved a lot more up the pitch, Alexander-Arnold was more involved in the initial build-up. Sometimes he would even move into the half space to create a back three alongside Joel Matip and Virgil van Dijk. Apart from that, we should point out that Matip was extremely active in the build-up and had more touches than any other player on the field (107).
Southampton defend tight and narrow
It was extremely difficult for Liverpool to create chances though. Even though their build-up was stable thanks to the described approach, the opponent wouldn’t leave any spaces.

Here, we see how Southampton built two massive defensive blocks. In front of the tight back five, there was a four-man line narrowing the midfield. Liverpool moved a lot between the lines, but it was difficult to get the ball there, simply because of the sheer amount of opponents nearby.

Theoretically speaking, Liverpool’s positioning was good. Here, we have an example where three players occupy the gap between the opponent, creating alignment problems for the midfield line. Roberto Firmino’s role as false nine should also help in having a superiority in the midfield when he falls back. Southampton is stable though. As soon as Firmino receives the ball, Maya Yoshida is able to move out and attack Firmino. Ultimately, he wins the ball and the attack is over. Playing through the centre was thus almost impossible for Liverpool.
Southampton were able to create a lot of problems for Liverpool
From time to time, Southampton also attacked higher and tried to press aggressively.

As we can see in this image, it was a strict man-marking approach. When Alexander-Arnold receives the ball, he has no passing option and is put under a lot of pressure. This scene resulted in a loss of possession, but Southampton weren’t able to convert it into a goal.

After winning the ball, Southampton were often able to start a quick counter-attack. Most of the time, Liverpool weren’t able to come back fast enough, so Southampton had superiority in the final third. Passes into the open space, like here played by Pierre Højbjerg for Nathan Redmond, were pretty dangerous, but the final pass or the finish were poor.

Also, Southampton were able to create at least numerical equality in the box in dangerous areas. This seems to be something Ralph Hasenhüttl has adapted from his former teams like RB Leipzig or Ingolstadt where he used a similar approach.
Liverpool with a good press apart from one situation
In order to restrict these dangerous counter-attacks, Liverpool relied on their great pressing abilities. As usual, they played it with high intensity.

We see a clear man-marking approach here as well. Unusual for Liverpool, we see no use of cover shadows, but rather a quite simple form. In many positions, this was enough, but one special moment showed that even a team that might be considered as the best pressing team in the world is not at all perfect at it.

Yoshida has the ball and Liverpool try to attack him. The ball was previously on the left defensive wing of Liverpool, where most of their players have shifted to. Thus, the centre is open. Left centre back Jannik Vestergaard seizes the opportunity and moves forward into the open space. He receives the ball and has a lot of time and space. So he creates a dangerous attack.

Vestergaard plays the ball out to the left wing to Ryan Bertrand. Liverpool aren’t attacking him, so Bertrand uses the time and space that is given to him. He crosses the ball inside, where once again Southampton are positioned well inside the box. Ultimately, Shane Long is able to score the opening goal.

Liverpool have difficulties finding solutions
Since there was no way to combine through the centre, Liverpool were able to adapt their tactics and play more through the wings. Before doing that though, they also tried to get behind the defensive line with long balls.

Here, Mohamed Salah starts a run behind the defensive line and Fabinho tries to pass the ball to him with a long ball. Since the defensive line is only 20 meters in front of their target, it shouldn’t be a surprise that this idea didn’t work out, because there was simply no space available behind the back line. So Liverpool started attacking through the wings.

One idea was to change the direction of play by switching wing with a long ball. Here, Alexander-Arnold plays a long ball to the other full-back Robertson. This makes sense, as the wing is wide open after Southampton has shifted to the ball-near wing.

Another idea was simply to play a long ball longline. This was increasingly used in the second half between Robertson and Sadio Mané. The two had a really good connection and were quite active in the second half. From a theoretical standpoint, one would admit that the longline ball has some weaknesses, as the opponent most of the time is already near the ball and doesn’t have to move at all. Therefore, instead of creating gaps, it seems that one play the ball into a tight area. Nonetheless, Robertson and Mané were able to execute this idea well.

Also, when Mané would move inside, he was able to get the ball back to the wing to Robertson, who then could build up tempo coming from behind. There were some situations where Robertson could make dangerous crosses.
In the end, the equalizer, as well as the third goal for Liverpool, were scored coming from the right wing. This is somehow ironic, as the left wing with Robertson and Mané was the more active one. However, it leads to the conclusion that attacking through the wings was important for Liverpool.
Deciding goal by Salah
The most important goal, however, was the 2-1 by Mohamed Salah scored in the 80th minute of the game. Interestingly, Southampton had one of their seven corners in the game. Then, all of sudden, the ball came to Salah near the halfway line, who then found himself in a one on one situation.

It wasn’t typical for Southampton to increase the risk so much, nor was it necessary. It appeared odd to suddenly see a position like that, but Salah remained calm and scored a goal that might be extremely important for the title fight. Without this clear mistake of Southampton, it would have been difficult for Liverpool to score the winning goal. After a double substitution in the 59th minute, with James Milner and Jordan Henderson coming in for Alexander-Arnold and Wijnaldum, Liverpool seemed to further increase the control of the game, but one must state that they had their difficulties.
Conclusion
From a neutral perspective, this game was quite interesting. Southampton played a really good game, but made a crucial mistake while having an own corner kick. Leaving Salah in a one on one situation decided the game. Apart from that, Liverpool were actively trying to find a solution against the two massive blocks of the home team, but the Reds had a hard life doing so.
Also, the dangerous counter-attacks of Southampton made it difficult for Liverpool. All in all, Jürgen Klopp will be relieved that Liverpool managed to get three crucial points in the title race.