Analysis: Irish scrum struggled against France, but Wayne Barnes' guesswork ruined the set-piece

That was messy. My God, was that messy.

After powering through Italy, the Irish scrum came back down to earth on Saturday.

However, things could have been far, far worse had the game not been officiated by the largely clueless Wayne Barnes, whose endless guesswork and complete lack of understanding about the set-piece produced some inexplicable decision making.

With both sides looking to put down a marker, Barnes needed to stamp his authority early, and the endless pushing before the ball from both sides went continuously unpunished.

We'll use the first scrum as an example. Note the yellow line, cutting through the middle of the pack.

And as Conor Murray feeds the scrum a few short seconds later, Jack McGrath has rotated the scrum a solid yard, but it's ignored by Barnes.

However, despite taking the nudge from the Irish pack, the French are in complete control once the ball is fed.

Mike Ross had a considerable weight advantage over his opponent Eddy Ben Arous (various websites say he's between 1.5 and 3.5 stone heavier), but as we showed in our French preview last week, while Ben Arous may be light for a prop, he proves that technique is often times better than power.

With the camera on the opposite side of the scrum, we can see that Ben Arous has a perfect scrummaging technique; he's low, with his back parallel to the ground and legs bent.

Compare that to Ross, who has locked out his legs fully, such is the pressure he's coming under from his opponent.

Both Jack McGrath and Mike Ross end up collapsing this scrum, and the penalty goes to France. McGrath falls to his knees, as we can see above.

While below, Ross also drops the scrum.

McGrath really shows his strength at the next set-piece shortly after though, after his opponent Slimani packed down way too high, and had the ball not flew out the back of the scrum so early, McGrath would really have turned the screw.

Note the difference in angles between McGrath and Slimani above. The Irish prop has got in (legally) under his opponent's chest, and left Slimani no choice but to go up.

He went a step further and won an excellent penalty for Ireland next time around, but before we get to that, we're going to have a look at an example of how little understanding Wayne Barnes has for the scrum.

Do me a favour. Stand in a squat position, and then bend forward, to simulate a front row forward. Now hold that position for 22 seconds. Legs feeling wobbly yet?

Before the day's third scrum, Barnes had the front rows pack down a full 22 seconds before he was ready to even call crouch, showing just how oblivious he is to the balance needed to keep a scrum stable.

We can see below that the clock is stopped at 9:40, when he marks the scrum, and the players get ready to pack down.

However, with Wesley Fofana still receiving treatment down the blindside channel, there is still plenty of time before we're ready to play.

And 22 seconds later, at 10:02, Barnes finally calls for the front rows to crouch. Inevitably, this scrum will collapse.However, this time it's Ireland who will pick up the penalty, as Jack McGrath gets hauled down to the ground illegally.

In the photo below, note how Slimani has once again made a mess of his body position, starting too high, and thus allowing Jack McGrath to drive under him.

To counter this, Slimani begins to bind on his arm, marked in the circle, while the X shows where he really should be bound.

As the scrum goes on and Slimani becomes under even more pressure, he pulls his right arm down, causing McGrath to turn in and drop to the ground.

Penalty Ireland.

The first half was solid, but it's from here things really went downhill for the scrums, and indeed for Wayne Barnes.

Both Mike Ross and Jack McGrath could, and should have been penalised on the opening drive of the half, but Barnes, and his touchie Nigel Owens, both seemed oblivious.

On Owens's side, Mike Ross took a clear pull at the arm of Eddy Ben Arous, circled, as he was clearly struggling to deal with the Frenchman's power, yet again needing to lock out his legs fully.

Barnes was keeping an eye on the openside of the scrum, and in reality, he could have been staring into a field of thistles, for all the use he was.

Below, we can see that Jack McGrath is boring straight across Slimani's chest, and despite the scrum collapsing because of it, Barnes waves play on, instead penalising Ireland at the ruck which followed.

Fortune continued to shine down on Ireland shortly after, as they won a free-kick despite Mike Ross spending much of the scrum on his knees.

After two collapsed scrums, we finally completed the second reset, as France's Bernard Le Roux was penalised for kicking the ball back into the scrum.

While we're not doubting that it happened, it's worth noting that Mike Ross had been on his knees for a full three seconds, which one of Barnes, or his touch judge Owens should have spotted.

Ross was looking ragged, and he gave away an inevitable penalty at the next scrum, not taking the hit and going straight to the deck, something not even Barnes was able to miss.

It was entering crisis territory at this stage, with replacement loosehead Vincent Debaty providing fresh pressure on Ross.

A second penalty against Ross was soon to follow, as he dragged down Debaty by the arm, and with it came a stern warning from Barnes about his binding.

We can see in the early stage of the scrum how Ross has a very short bind, with his arm pointing to the floor, a tell-tale sign that it needs to be longer.

Despite France being a man down after Pascal Pape's yellow card, they put Ireland under more pressure, resulting in Ross dragging down the set-piece, his final act in a disappointing scrum performance.

Barnes took to guessing quite a bit at the scrum, and this was the example that probably summed up his day.

There is one big element that distinguishes a legally wheeled scrum from an illegal whip, and it all revolves around the scrum's axis.

For a wheel to be legal, one side of the scrum has got to move forward, and despite the French doing just that in the 66th minute, Barnes didn't seem to think so.

In this first photo before the feed, keep a note of the initial position of the scrum.

As the scrum progresses, Vincent Debaty begins to get the nudge on Marty Moore, and drives forward, while the mammoth Uini Atonio holds his position, acting as the anchor.

And the scrum continues to wheel, eventually passing through 90 degrees, which should result in a turnover for the French.

Instead, Barnes judges that the French have illegally whipped the scrum around, and the penalty goes to Ireland.

Shortly after, we see a similar incident, although this time the scrum is illegally whipped by Ireland.

However, Barnes again gets it wrong. He ignores the Irish whip wheel, instead penalising Cian Healy for a crooked drive, despite Healy clearly scrummaging square and straight.

First though, we'll look at the whip.

As we did last time, we'll look at the initial position of the scrum as a starting point.

Once the ball goes in, the scrum begins to turn, but it's the French who are moving forward of the axis.

And when the scrum eventually moves past the 90 degree angle, we can see that the Irish pack have swung the scrum even further, but that they haven't actually moved the scrum forward.

Watch it through in GIF form, and follow this little step. Place your finger above Cian Healy, and watch the scrum rotate around it. No forward movement, so therefore it's a whip.

However, Wayne Barnes being Wayne Barnes, he happened to spot a phantom offence, rater than the one that was staring him straight in the face, penalising Healy for a crooked drive, while this photo clearly shows that he is driving both straight and square on his opponent Atonio.

Guesswork, a close ally of Wayne Barnes.

In the November win against Australia, Ireland struggled badly in the scrum before fronting up late on, and it was in the closing minutes that they produced two of their best scrums of the day.

It was a similar situation on Saturday, with the previously ragged frontline holding firm for the day's most crucial drives.

This first was a fine defensive effort, as Marty Moore kept square and low, with great support from Peter O'Mahony, keeping the scrum stable at a time when it was badly needed.

The game ended when Simon Zebo and Sean O'Brien bundled Remi Lamerat into touch, but it should have been all but over after the final scrum, when Ireland were somehow not awarded a penalty.

Again, Marty Moore sets the platform, showing off impressive angles, and keeping the scrum steady.

The pressure from Moore was too much for Benjamin Kayser, the French hooker popping out of the scrum and standing upright, but Barnes didn't have the bottle to penalise an attacking scrum so late in the game.

And Barnes continued to turn a blind eye when Debaty joined him in standing upright. Two huge late scrums from Ireland.

With England to come in just under two weeks time, Joe Schmidt will have a big decision to make at number 3 on his team sheet.

Mike Ross was outstanding against the Saxons and Italy, but seriously struggled against his more nimble French loosehead. He'll be up against Joe Marler in two weeks, who destroyed him (whether legally or illegally), when Leinster met Harlequins in December.

Marty Moore is the other option, although the 23-year-old is still very raw. He looked in trouble early on last weekend, but fronted up late on to hold the scrum together.

And he could well be a wildcard selection for the visit of the chariot.