Why is Georginio Wijnaldum so important to Liverpool?
Take a look at Georginio Wijnaldum's stats at CM from the Premier League this season, and at first glance you might not think he was such a great player, let alone a pivotal one:
His attacking output is low for a CM, he doesn't seem to defend much, and he's a weak finisher in open play. But look more closely, and you can see that his ball retention has risen steadily over the past few seasons, and he's an outstanding tackler. And this is where we start to see Wijnaldum's utility.
Next, let's look at his smartermap at CM for this season:
He operates primarily on the left, going much closer to the flank than a prototypical Premier League CM like Paul Scholes, Frank Lampard, or Steven Gerrard. But that's something he has in common with all of Liverpool's CMs. Wijnaldum and Naby Keita stay to the left, while Alex Oxlade-Chamberlain and Jordan Henderson (when he plays further up the pitch) hug the right-hand touchline. This facilitates Liverpool's somewhat unusual formation, which offers space for Roberto Firmino to operate deep in the central channel – and Wijnaldum typically leaves more room in the middle than the other three.
A direct comparison of Wijnaldum, Keita, and Oxlade-Chamberlain offers another hint to Wijnaldum's special role:
Keita looks superior to Wijnaldum is just about every category except ball retention, where Keita is still very strong. Indeed, Keita is the same all-action two-way player that he's been at all of his clubs. But the problem is that this isn't necessarily what Liverpool need at CM on the left side.
The reason for that comes down to one player: Sadio Mane. If Mane's on the pitch, then many times Keita charges in from the left side and shoots, it's a shot that Mane isn't taking. As you'd expect, Mane is better at generating opportunities and takes better shots than Keita, averaging an estimated chance of scoring around 20% while Keita is down in the teens. Mane is also a much better finisher, rating 67 for non-headers in open play among wingers versus Keita's 32 among CMs (and you can guess which scale is tougher). So Keita's extra shooting could be crowding out Mane's production. Of course, this assumes that if the CM on the left doesn't shoot, the ball will get to Mane – and with Wijnaldum's ball retention, it's almost a guarantee.
Liverpool aren't the only club to have a CM playing this role. If we look for other CMs with low attacking output and extraordinarily high ball retention in Europe's top five leagues, another club pops up a few times:
Arthur, Frenkie de Jong, and Ivan Rakitic all play for another club with exceptional forwards. The key for Barcelona is to make sure their forwards get the ball. Don't get us wrong – a player like Keita can still be a huge asset, especially given his ability to win the ball in dangerous positions. But given how the Liverpool machine works, sometimes a reliable link who's also capable of making a choice tackle is what's needed most.