Analysis: How Faf de Klerk blows up set-piece plays before they even get started

Last year Faf de Klerk’s defensive role was compared to that of an NFL free safety, all about disguise, surprise, and pressure, roaming freely around the secondary or blitzing off the edge to cause disruption.

The autonomy of his role in defence is quite extraordinary.

He defends in the front line around ruck channels during phase play and on the edge following lineouts and on the goal line.

He drops in-and-out of the sweeper role as he sees fit and pressures ball carriers by rushing out of the line. He even ‘sacks’ opposite halfbacks, blitzing through ruck channels with anticipatory foresight.

There is an extension of this role at scrum time, which often has a big impact for the Springboks.

The sheer speed at which he takes away space and time often limits the opposition, and can still hurt even if he doesn't force an error or turnover. His presence can be suffocating and cause plays to break down before they really start.

Set-piece pressure game

To understand what Faf brings to set-piece scrum defence it helps to see what can happen without him involved.

In the recent warm-up match against Ireland, England has an empty blind with Jonny May (11) stacked behind George Ford (10) as Billy Vunipula (8) looks to dig out the ball out of the scrum.

Ben Youngs (9) is already pushing off the base awaiting Vunipola’s pass.

Ireland already have adequate protection on the blindside should Billy Vunipola carry that way.

Peter O'Mahony (6) will naturally break that way, followed by CJ Stander (8). Jordan Larmour (14) also can be a third defender dropping down from the backfield.

Vunipola may find easy metres with a strong carry but anything more is unlikely, with the Irish defence closing him down around or outside the 22.

Ireland’s focus, especially Conor Murray’s, should be on Youngs especially since the blind winger May is already on the open side. Ireland are going to be emphatically outnumbered if Youngs can reach and engage Ross Byrne (10) and find a way to get May involved.

Conor Murray (9) inexplicitly bails to the blindside just as the pass is delivered to Youngs, leaving an open highway for the English halfback to set this open side play in motion.

Youngs has all the time in the world to attack the space in front of him while Murray is left with his hands in his pockets kicking stones behind the scrum.

England run freely at the Irish backline, freezing young flyhalf Byrne and forcing the rest of the defence to collapse in. The slick handling frees up Joe Cokanasiga with the last pass to score in the corner.

England had problems executing similar plays in South Africa last year with de Klerk patrolling the base instead.

De Klerk has explosive off-the-mark acceleration and is able to pressure Youngs immediately, forcing an early pass that throws the timing of the play off.

Owen Farrell (12), meant to be running a flat option off Youngs, is the first to be made redundant by de Klerk's pressure allowing the defence to rule him out early as an option.

Ford (10) is stationary receiving static ball, throwing out Henry Slade’s (13) timing, who is now front-running the flyhalf.

As Ford looks to his outside, the play has short-circuited causing hesitation and indecisiveness. He freezes up momentarily before deciding to cut back and is absolutely lit up by de Klerk flying through like a heat-seeking missile.

The supporting England players Slade and Tom Curry are at risk of being penalised for side entries trying to backtrack around to secure the ruck. They escape punishment on this occasion, despite coming in from the side.

De Klerk blew the play up by forcing an early pass with pressure on Youngs which threw the timing out, but secondly by staying alive and continuing his path of destruction towards Ford, tackling him for a loss and putting England in a compromised position which should have led to a penalty.

It’s his relentless effort that powers a high-pressure defence system to take away time and space from the attack.

Argentinian halfback Tomas Cubelli (9) is able to get away a backhand flick pass despite being in the jaws of de Klerk’s tackle.

In the same way he was able to pressure Youngs and bury Ford, he releases Cubelli in pursuit of Nico Sanchez (10) to stay alive and further influence the play.

The flyhalf's internal clock is always ticking as de Klerk is always 1.5 seconds away. This leads to passes being pushed early, giving the Springboks outside backs more time to make their reads and an easier job in defence.

Not only does de Klerk constantly disrupt the flow, but he also stacks the odds of the Springboks closing the play down in their favour by staying alive.

TJ Perenara (9) is forced to provide a quick release from the base with de Klerk bearing over him. The All Blacks look to use simple hands to exploit numbers to the left.

Richie Mo’unga (10) gets the ball away to the next man but doesn’t escape de Klerk, wearing a shot to the ribs from the physical halfback.

Mo’unga falls to the ground while de Klerk stays up, removing any chance the flyhalf has of getting a second touch with inside support play.

With one less supporting player and de Klerk still in pursuit, the Springboks have a better chance of shutting down the situation. Against the All Blacks who kill teams once a line break is made, limiting the numbers of support players can save seven points.

If de Klerk has identified the play type, he may risk fully committing to the tackle in order to blow it up.

Reading the ‘8-9’ pass off the base, he explodes off the mark with a bee-line for Cubelli, the identified playmaker on the move.

Cubelli has no space to eat up in front of him and is crushed by de Klerk before he can challenge any defenders in the backline.

His pass is far too early for his midfielders who were expecting to be flat options much closer to the line.

The resulting ‘lollipop’ pass sails behind inside centre Jeronimo de la Fuente (12) while Matias Moroni (13) has to completely stop and catch the ball facing the sideline, with the play dead and buried.

De Klerk diagnosed a ‘halfback taxi run’ to the open side and went full bore to kill the move before it got started.

The play was likely a long 'tunnel' ball from the halfback behind 12 & 13 to the reserve flyhalf coming into the left of the screen with the blind winger. Without the time required to execute, Cubelli had to bail on the play and try and hit de la Fuente (12) early instead.

De Klerk has the ability to ruin every opposition scrum play that relies on 8, 9, 10 in a 'playmaking' or carrying capacity. That includes exit situations with a high likelihood of an '8 carry' off the back.

That has a very real impact on the ability of teams to strike from the scrum platform, especially for teams that are using their halfback in a playmaking capacity in the early stages of strike plays as England did against Ireland.

Against the Springboks with Faf de Klerk, the play won't even get off the ground. His persistent pressure and aggressive blitzing is killing plays before they even get started - an extremely valuable asset to have in limiting scoring chances.

At the World Cup where defence will be critical, having a trump card like de Klerk is going to have a highly underrated impact.

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