Six Nations Championship Ireland's tactics: St Valentine's Day Massacre, the headlines might scream if Ireland take to the Parisian challenge at Stade de France today with their traditional aptitude. It'll be just another Irish gang left bloodied and cowed, ambition shredded in a grisly end to a turf war.

Diet-Ireland head for the Parisian capital, the absence of several heavy-hitting front-line players having reduced the national side to a slim-line version. It doesn't augur well. History is littered with examples of French bloodletting at Ireland's expense.

Therefore when Ireland's defensive coach Mike Ford and forwards' coach Niall O'Donovan take their places alongside head coach Eddie O'Sullivan and his assistant Declan Kidney, there are few who would envy them.

Ford is charged with masterminding the corralling of the French on home soil while O'Donovan must foil one of the best set-piece teams in world rugby.

Down the job centre these rank with captain of the Titanic.

Just as well both share a sense of humour and are known not to shirk a tough challenge. Ford smiles when asked to assess the French defensive system, one O'Sullivan and not the Englishman will be asked to unravel.

"They try and intimidate teams who then get frightened to go around them. It's this blue wall that sucks teams into it and the three-man tackle that makes it very effective. When they do it right from the next phase it's very difficult to do anything other than kick it. If you do hang onto the ball through a few phases, you find that you're losing a lot of energy not to go anywhere."

System wise, Ford doesn't believe it's as good as the Irish version that will be unveiled today. He's not being boastful just honest but he does counsel: "The athleticism and speed, strength and technique (of the French players) are ahead of us. The French refer to the blue wall as their engine room and they challenge you to get around it. That's what we are going to try and do this weekend.

"The first hit from any set-piece can wrest the momentum for your side. (Serge) Betsen is the guy who does that from a lineout; a very, very good defender. The other two Imanol (Harinordoquy) and (Olivier) Magne are more the runners. It's a very well balanced back row. Michalak is not the greatest defender in the world so I expect Betsen to act as his bodyguard."

Ford's primary concern and responsibility will be when France have possession. "You pretty much know what they are going to do. There are a few triggers there to tell what they'll do in certain situations. The fact is they do it very well, the basics."

Today at Stade de France, Ireland will unveil the new defensive blueprint.

Ford explains: "We have tweaked our system this time. Part of it is down to playing France but we are going to carry that bit of a difference through the Six Nations. I am pretty much happy with this system.

"Where England, for example, have got us is that they slow down the ruck ball very well. Their contact is good and then they have the experience of getting hands on the football and coming over the top. It's not necessarily illegal, it's just that they push it to the Nth degree.

"France regroup quicker (than we do). What we have to do is go forward quicker (when defending) with a better technique. I am confident that once we do get good tackles and a slow ruck, we will take some breaking down." He points out that all attacking teams crave the same thing, "a soft defensive shoulder," that offers the first chink in a line of defenders. "It 's like a domino effect. The next tackle is even weaker than the first and so on because you can't regroup properly in the line."

Traditionally Ireland have probably been among the worst broken-field defenders. Once the first line is filleted, it tended to pre-empt a try. Ford acknowledges a significant improvement was required. "We've done a lot of work on play what you see, play what's in front of you. We have worked on field recognition, applying that to defending differently depending on field position.

"If you have backs or forwards with you or against, the numbers defending or attacking; all these things have to be processed quickly and a decision made and communicated. If they can recognise quickly what's in front of them then they should know what type of defence to use. There are variations. It's about making a decision, you can't defend on your own. Communication is essential.

"If you go back to the first try in Melbourne (in the World Cup quarter-final). From a seven-man lineout, they went wide off the top. Our enthusiasm was unbelievable, probably too good. So we had eight or nine defenders chasing and they got us with a cross field kick. We have fixed that now. It's that recognition. At what point do you say 'I'm not going to chase this I'm going to go back into my line'. It's that sort of decision-making that we need."

Ford agrees the players can be led to the trough but not made to drink. They must think for themselves and react to events on the pitch. The system is the parameters in which they operate.

"Even if it's the wrong call, we do it together. When one rushes out and one stays back thats when the gaps appear."

O'Donovan faced a similarly tough challenge in preparing the Irish pack for today, especially as he was taking over as scrum doctor following the departure of Tony D'Arcy. The video of the World Cup quarter-final was a useful tool. He recalled the first two scrums of the match when the French shunted Ireland off their first two put-ins, establishing momentum and the psychological edge.

"The knock-on effect of the scrum going wrong is the mauling and lineouts can go astray. Your confidence is down because it is the first time that all eight forwards go against each other. If you come second in that, the knock-on effect is huge when it comes to other aspects of forward play.

"This week we asked questions of the individuals in the pack and to this point they have come up trumps. The French are unrelenting at scrum time . . .Today it means breaking it down to one scrum at a time, concentrating on getting that right. The scrum is an attitude thing."

The lineout? "France have one of the best in the world because of the athletes they have within the team. They have four jumpers who can move up and down the line and are a huge threat on opposition ball. They have four guys to watch our three."

Are lineouts a bit like playing poker?

"Definitely. "It's also about speed. Speed along the ground, speed into the air. We'll try and keep them on the ground until the ball is released."

O'Donovan knows that all the preparation becomes redundant if the players can't implement it. He won't be there to chivvy and chide. Like Ford he must confine himself to the stand, hoping training ground precision doesn't wilt in the Paris sunshine.