'While South Africa were tremendous in the final, if they played five times, England would win four'

Thomas Castaignede believes England were the best team at the 2019 Rugby World Cup, but is backing “x-factor” scrum half Antoine Dupont to provide the magic to give France victory in their Six Nations opener at the Stade de France on Sunday.

With Dupont threatening from scrum half, Castaignede is confident a young French side under new head coach Fabien Galthie can shock the World Cup runners’ up and sees this match as their best opportunity for victory over England. He told RugbyPass: “Antoine Dupont is the x-factor - someone who can create something special and he will have to be watched by England because he can get inside any tiny hole (in the defence).

"He is uncatchable and I would describe him as a French player with a English mentality!

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“This French back line is probably one of the most exciting in the World and if you take every individual they are at the top level and only Anthony Bouthier at full back doesn’t have a lot of experience but has shown with Montpellier that he has this energy – a craziness – that could make the difference. He is a speedy guy and he will get tested by the high ball which means the wingers have to help him.

“Fabien wants France to play without fear and not concentrate on what England are doing. Before when we played England we only thought about counter-attacking because we knew they were better than us. This could be a good time to play England who haven’t played together in a long time. They should have won the World Cup because they were the best team and the semi-final win over New Zealand was fantastic and while South Africa were tremendous on day, if they played five times, England would win four.

England players look on while New Zealand perform the haka in Yokohama. (Photo by Cameron Spencer/Getty Images)

“For some of the players from Saracens, mentally it must be tough and if you are not 100 percent committed then at the highest level you can be punished and if there is a time for France to beat England then it is Sunday. “

Castaignede, who won 54 caps, does see a potential weakness in the French pack and it revolves around the South African-born pair of locks Bernard Le Roux and Paul Willemse, who lack the mobility of their opposite numbers. This could be damaging if England are able to win quick ball and replicate the rugby that defeated the All Blacks in the semi-final in Japan.

“My main concern is the mobility of the front five forwards because so many teams have second rows who get around the pitch like back rowers and still hit 20-30 rucks:” added Castaignede.” It means you almost have a back row of five players and while le Roux is a quality player and good in defence, he doesn’t connect in attack as much and I still have some concerns. Willemse is someone who may be a bit too heavy for the position and they both need to improve.

“In the front row, Mohamed Haouas is a strong No3 which you need, but it is difficult to also be a good runner as well and he may be changed after 45 mins.

"The other two, Cyril Baille and Julien Marchand, are very good players and cheeky players and remind me of Christian Califano and Rafael Ibanez. They could play in the backs and make the right decisions at the right time and know each other really well playing together at Toulouse.”

The former Saracens and France full back has seen much needed improvement in the relationship between the national team and the Top14 club since Galthie was appointed and pinpoints the arrival of former national captain Rafael Ibanez, as team manager, as another big plus. “I am very excited like everyone else and Fabien has been trying to create a better contact with the clubs and the link is now stronger than before but not as it should be.

“There is still a long way to go and Fabien is the tactician and Rafael is the social communication guy and as a captain knows how to deliver the right messages. They are a good combination because Fabien can sometimes be very hard with himself and some of the players and Raf is there is deliver things properly to the players including team spirit that in the past has been lacking not because of the players but due to the results. Without the right results it is difficult to be united and confident when you know that in the next game you may not be playing.

Paul Willemse (Photo by David Rogers/Getty Images)

“They will succeed and it will be interesting to compare after two years how many players Fabien picks compared to the same time under Jacques Brunel and Guy Noves. The players who have been picked are performing very well in the Champions Cup and dominating, especially in the backs.”

Castaignede is a fan of England head coach Eddie Jones and has seen his prediction that they will play the greatest rugby the world has ever seen. “I hope they do play like that otherwise it will be embarrassing he said that: “admitted Castaignede. “I know Eddie and he likes to say these things because he wants to be under pressure and wants it to push him and the players. Tactically it is well played by him by saying “ we will be the best team in the world and play the best rugby” and this will be a massive test. If you lose two or three games for England then you can be sacked and so he has nothing to lose saying it.”