Liverpool's 2-2 draw with Swansea City was enough to keep the Reds top of the early Premier League table on Monday night, despite the Reds losing their 100 percent record in the process.

Victor Moses caught the eye with a debut goal, but another debutant, defender Mamadou Sakho, seemed to split opinion over whether he had enjoyed a promising first appearance in a Red shirt or a poor one.

Ok. Sakho messed up this time. Still doesnt mean he's poor though — Alexey Yaroshevsky (@YaroLFC) September 16, 2013

Sakho was a bit shaky but plenty of glimpses of what we can expect and I, for one, am excited. His last ditch tackle at the end was boss. — Jeff Magnier (@jeffmagnierLFC) September 16, 2013

It's easy to say that the real answer is simply "somewhere in the middle," but we can look closer at what Sakho did well and why he did the things perceived as mistakes along the way.

Starting right at the beginning, before the game even, it became apparent that Sakho did not have an awful lot of time to prepare for the match knowing he was starting.

Daniel Agger travelled with the Reds to the match in anticipation of playing, which would have left Sakho on the sidelines, but the late decision was made not to risk him after a minor knock. Not having time to think about his debut could work either way for Sakho, of course, but he certainly had a difficult start.

Within two minutes of kickoff he had failed to clear a header sufficiently far out of the box, missed a tackle on Jonjo Shelvey and then couldn't track back quickly enough to make a block—and thus, the opening goal of the game was scored.

The French defender settled down though, as did the team in general after the quick-fire equaliser, and defensively he was largely sound—beyond sound, in fact—for the remainder of the match.

With regards to central defenders, there are several different aspects of their game which can be analysed.

There is the technical side: how they fared with their challenges, their clearances and so on—their defensive work, in other words.

Afterward we also have their positioning, how they fared within the team structure, whether they were part of a cohesive defensive unit and whether they were able to, positively or negatively, influence their teammates.

Finally, there is a decision-making aspect of the game that can be looked at, at least in part, and which ties in to both of the previous two areas.

All factors require an element of guesswork to a certain extent, as from the outside we cannot be sure of the tactical instructions given to the players before matches. Previous games and a knowledge of the preferred methods of playing certainly limit the amount of estimation that needs to be applied.

So how did Sakho fare as the defender which he, first and foremost, is?

Remarkably well.

Unfazed by the talents of Michu, the power of Wilfried Bony or the pace from the flanks in direct combat, Sakho was in fact one of the most important elements of Liverpool's back line holding Swansea at bay, especially during the long periods in the second half when the Reds lacked possession.

With Swansea making just over 200 passes more than Liverpool during the course of the game, there were ample opportunities for the home side to put the ball into the box. Although renowned as a passing, probing side, the Swans are not afraid to utilise crosses, especially low or mid-height ones, and put no less than 26 into the Liverpool penalty area.

Sakho was one of those who was constantly repelling these balls into the penalty area, as well as stopping through balls before they reached their target. His tally of 15 clearances in the match—all of which found a red shirt—shows his impressive reading of the game and capability to defend different match situations.

The same was true for one of his two attempted headers and both of his attempted tackles, the latter being one of paramount importance late in the game to deny Michu a clear run on goal.

Alongside his clearances reaching a teammate each time, Sakho misplaced just two of his 41 passes during the course of the match, finding a red shirt 95 percent of the time. Neither were they always simple, short or sideways balls, as the ex-PSG defender displayed a willingness to move into midfield and search out attackers with penetrating passes.

In both of these regards, we can ascertain that his in-game decision-making is largely good when he is on the ball or required to physically undertake defensive action—with the notable and regrettable exception of the opening-minute fiasco leading to Shelvey's goal.

Positioning, however, is another animal entirely.

Whereas positioning the body in a certain direction to control or clear the ball is instinctive play—able to be improved by training, sure, but first and foremost a natural appreciation of movement and balance—positioning within a defensive line is something which requires intensive practice.

The reason being, of course, that team to team and game to game, there are a vast array of decisions that can be taken in response to each type of attack being faced.

For Sakho—or Kolo Toure, or Martin Skrtel, Agger, Tiago Ilori or whoever else is playing—to function effectively and seamlessly, time on the training pitch is going to be needed, as well as a regular run of games with, hopefully, an established partnership at the back.

Just four games into the Premier League season, the Skrtel-Sakho combination that faced Fulham was already Liverpool's third centre-back pairing in front of new goalkeeper Simon Mignolet.

It was therefore natural, understandable and always likely to happen that Liverpool had a few issues with regards to positioning and decision-making for defensive movement.

Take a look at Sakho's position for the buildup to Swansea's second goal:

Here we clearly see, just as Shelvey is about to head down the assist for Michu's equalising goal, the No. 17 in a more advanced position than partner Martin Skrtel, who has had to drop deeper to cover the gap behind Sakho.

This was a common and repetitive feature of the Frenchman's debut.

Whereas the ideal scenario is to maintain a solid, flat and compact back line of defenders, Sakho frequently pushed out to close down the space ahead of him, just prior to a through pass being made or a ball being played higher or longer toward the Swansea front line.

Is this his fault? Is it, indeed, an error from Sakho?

Let's run back the feed a few seconds and see what influenced Sakho's decision to break ranks.

This still image shows how Liverpool's midfield had become lopsided, with three of the four middle players bunched on the right of centre. With Victor Moses wide on the left, that left a large space in front of the Liverpool defence on the left-centre side of the pitch.

Swansea have two diverse forwards in Michu and Bony, but one trait they both share is an excellent appreciation of how to use space. Both forwards, at this instant, dropped off the shoulders of the Liverpool defenders into the gaps between midfield and back four, with Bony—on Swansea's right, Liverpool's left—able to pick a position in space to receive the ball.

This immediately gives Sakho a dilemma: to hold his ground, let Bony turn and run toward goal, or to chase in, close him down and force a decision from the Swansea man?

Sakho opted to close down and with Skrtel alert to the situation that could have been enough for Liverpool to survive, a long-standing weakness once again presented itself.

Consider the first point: no runner tracking the movement from deep from the opposition.

Now look back at the middle image of the three, with Shelvey about to pass the ball. He is at least 10 metres, perhaps more, in front of the three Liverpool defending midfielders. Scroll back up to where the first image shows Shelvey nodding the ball down to Michu.

That's around 30 or so metres of ground covered, in the space of about five seconds during the game...and not one of the Reds' three midfielders are even in shot by the time of the assist.

Yes, Mamadou Sakho made the decision to break out of the back four and left Skrtel isolated.

But the goal was not of Sakho's making. His decision was forced by one repetitive weakness of the Liverpool squad—poorly positioned holding midfielders—and compounded by another.

There are other reasons for his continual breaking out of line. Sakho is used to playing a high defensive line, and it is perfectly reasonable that he has been able to close down quickly previously because his own pace, and perhaps that of a partner at the back, is enough to cover a shortfall if the ball isn't won.

Whether Liverpool manager Brendan Rodgers wants him to continue that process of pre-empting attacks—or whether he has to settle in to learn to drop deeper on these occasions to protect the goal rather than the defensive territory—is something that will come with practice time and matches.

He will need to learn fast the Reds' way of defending, especially given the huge competition for central defensive spots at the club suddenly, but there is little evidence to suggest Sakho performed incompetently in any way after those tough opening moments.

He made decisions that he might have to alter his process of judgement for, but that is natural when moving to a new club, for any position.

But, perhaps importantly, he didn't simply do nothing. Sakho did not merely wait to see what transpired, and react to it, but instead tried to pre-empt the situation and be proactive in his defensive work.

At 23 years old he is experienced for his age, yet inexperienced overall. He is in a new league, a new footballing culture, a new language and against new opponents. With respect to Ligue 1, he is now against a better average quality of opponents.

Sakho will get better through natural progression, assuming hard work and good coaching, and he will get better at decision-making through gaining more experience as he goes.

But for a debut, being thrown in at short notice and coming up against one of the better attacking sides in the league...that wasn't a bad start for Mamadou Sakho at all.

Good things lie ahead for the Liverpool defence with him at the heart of it, and there are other areas of the side which yet need far more attention.

Follow @karlmatchett

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