THERE WAS A game-changing substitution midway through the second half of Ireland’s first test against South Africa.

In the seven scrums prior to Tendai Mtawarira coming off just before the hour mark, it had been one-way traffic.

On South Africa’s own feed, their three scrums had yielded a penalty, a penalty advantage (which led to Lwazi Mvovo’s try), and a comfortable in and out (ruined, though, by a Duane Vermeulen knock on).

On defensive scrums, they’d also been dominant, forcing turnovers on each of Ireland’s opening two scrums.

The problem is that all of the damage was being done by Mtawarira, and his replacement Trevor Nyakane is far from a Beast. When he came on, 58 minutes into the game, the balance of power shifted in Ireland’s favour. Even with Andrew Trimble plugging a hole in the back row.

For almost 60 minutes, South Africa dominated the set-piece, with an aggressive engagement a big factor.

Needing Trimble to lie in as flanker was obviously a disadvantage, but this third minute scrum shows that even with CJ Stander at blindside, Ireland were under serious pressure, conceding a free kick after Conor Murray’s reluctance to feed the scrum.

The reason it took Murray so long was the power being applied by the Springbok pack.

A regular tactic of Ireland’s (and most teams these days) is to have the hooker bring his foot forward, allowing the scrum half to place the ball behind it. It’s an illegal move, but one that’s so common and so rarely policed.

In the still below, we can see that as Murray taps Best with the ball to say he’s ready to put it in, Best isn’t ready for the feed.

The likely reason is because that there’s so much pressure coming from the South Africans, lifting his leg could destabilise the scrum.

Eventually, Best does bring his leg forward but by this stage, Murray had been standing beside a stable scrum for several seconds and referee Mathieu Raynal’s patience is worn.

The funny part is that when it happened in real time, my initial assumption was that we had finally seen a referee clamping down on pre-hooking in the scrum. However, watching back, he can be seen to tell Murray it took “too long”.

If Ireland were under pressure, Stander’s red card made the task all the more daunting, with Trimble standing in for all but two of the remaining scrums.

South Africa had the put-in to the next scrum after the red card, and as expected, they dominated it.

A trend in a lot of the scrums on the day was the Springboks’ pack trying to bring back an old-fashioned engagement.

Since the introduction of ‘crouch, bind, set’ a couple of years ago, we’ve seen the removal of the traditional hit-and-chase process, where the front rows would almost wrestle for position in the early stages after the engagement.

We can see below that the South African front row set very aggressively, and it immediately puts Mike Ross on the back foot.

As we all know, it’s illegal to drive before the ball is fed but in the grand scheme of things it’s a fairly minor infringement and if done correctly it can provide teams with an excellent platform.

It left the entire Irish pack off balance and on the back foot, and once the ball was fed and they started to push even more, we can see Ross falling to his knee.

In the still below, we can see the point where Ross hits the deck.

The Beast is a ruthless scrummager though and he continues to drive, maintaining a perfect body position, sending all of his power square through Ross.

We can also see just how disjointed and off balance the Irish pack are from being attacked on the engagement.

Some bodies are driving up and others driving down, while the South Africans are all moving straight.

So much of this comes down to that initial yard South Africa stole on engagement. It’s not legal but, if done subtly, it can be very effective.

Ireland’s second put-in once again yielded a South African free-kick for a delayed feed, but this time it does look like a little bit harsh.

Just like last time, the South Africans go in really aggressively on the engagement, stealing half a yard, just enough to disrupt Ireland.

Both Ross and Mtawarira are wrestling for position on the near side, and just as Murray is ready to feed, the pair collapse.

It’s one of those occasions where one is just as much at fault as the other.

As we can see, neither have slipped, but rather slowly drifted towards the ground.

They’re both using very short binds, and as a result they both have a role to play in the collapse. Trimble’s bind on Ross’ jersey may also have added to the downward pressure.

However, while Murray spots the collapse and holds off on putting the ball in, Raynal hasn’t spotted it, and awards another free-kick to the Springboks.

Had he seen the collapse, a reset may have been more appropriate.

The Boks opted for a scrum of their own, and it proved to be crucial, as they walked through Ireland, earning a penalty advantage, before Lwazi Mvovo touched down under the posts.

If we look at how they set up, everything seems fine. Everybody is lined up straight and square.

However, as Mtawarira gets a nudge forwards on Ross, the Irish tighthead gets dipped, and seems to drop towards the ground.

And after that, we can see that the scrum folds in, with the Irish pack starting to wheel around, bringing on the advantage.

Now down to 13 players, and desperate for half time, Ireland got a crucial bit of luck at the next scrum, when it looked like South Africa were ready to attack from deep.

Again the Beast had put Ross under pressure, as we can see with Ross beginning to stand up.

But with a two-man advantage, they aren’t hanging around in the scrum, instead trying to get the ball wide. However, in their haste, Vermeulen knocks on.

And it proves to be crucial. After their tactic to get an early push on Ireland had been so effective previously, they were eventually penalised by Raynal on the resulting scrum, which allowed Ireland to get into South African territory and kick a vital drop goal.

After regrouping at half time, it seemed that quick ball had become a major priority for Ireland on their own feed.

At the first scrum after the break, a quick channel one ball gave them their first completed scrum on their own feed so far in the game.

With Trimble still at flanker, communication was going to be key and we can see Jamie Heaslip explaining his plan to the Ulsterman as they prepare to set.

And once the ball is fed, we can see why Heaslip and Trimble were so deep in conversation.

Just as the ball goes in, Heaslip slides to the left in between Iain Henderson and Trimble, making it easier to get the ball as soon as it comes down the channel.

It was a little messy, but it did the job and the communication with novice flanker Trimble was vital.

It was the last scrum of the day for Mtawarira, and although he played the guts of an hour in a test match he really should have stayed on longer.

His replacement Trevor Nyakane came on to the pitch at the exact same moment as Tadhg Furlong, and Nyakane barely gave the Leinster tighthead a moment’s stress.

The double substitution changed the dynamic of the scrum immediately, as Ireland walked straight through the Boks, and earned their first scrum penalty.

While Jack McGrath was the one who did the damage, Furlong was comfortable on Nyakane.

We can see just how well McGrath does on Frans Malherbe. McGrath is driving straight and square with his back parallel to the ground, and all his power coming through his legs.

Malherbe, on the other hand, is in a mess. His head is way above his hips, and he’s under enormous pressure.

McGrath keeps driving and eventually it causes Malherbe to drop to his knees.

And if we watch it back in full, we can see just how dominant McGrath is.

The penalty went to Ireland and it could have got even sweeter; Paddy Jackson’s kick hitting the post.

Of the remaining scrums, it was comfortable for Ireland, but that doesn’t suggest they found a magic fix for their previous troubles.

They’ll have to face the Beast again this weekend, and barring injury, probably the week after that.

But it’ll be Tadhg Furlong opposite the Beast this Saturday, and a debutant second row behind him in Quinn Roux, making it a big gamble in one of the most crucial areas of the pitch.

It’s a gamble probably worth taking though, on Furling at least. Ross has come off a clear second best in his two previous games opposite Mtawarira,and if we want Tadhg Furlong to become the heir to the number three shirt, it’s an enormous opportunity for him to prove his Test credentials.

Slaying the Beast might not necessarily be an option, but if they can make it through 50 or 60 minutes some way intact, Furlong and Finlay Bealham can take a real cut off Nyakane, who’s just not in Mtawarira’s league.

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