Ireland coach Joe Schmidt and his players will be hoping that it is fourth time lucky in trying to close out a Six Nations Championship title on points’ difference. On three of the previous four occasions that it has been used to determine the tournament winner, Ireland, have lost out.

The Irish side (81) head for Paris on Saturday in a three-way battle for the Six Nations with England (32) and France (3) knowing that a victory by any margin is likely to be good enough, albeit aware that they have only won once there (2000) in 41 years.

In 2001 England and Ireland both finished with four wins in a tournament that was disrupted by the outbreak of Foot and Mouth disease. It followed that the last game was played in Dublin in October of that year with England having the chance of a Grand Slam having four wins from four and a Points’ Difference (PD) of 155. Ireland had three wins and a PD of 34, meaning that the home side needed to win by 61 to take the title; Ireland won 20-14.

In 2006 France and Ireland both finished with four wins. After the fourth round of matches France and Ireland were tied at the top on six points with PDs of +58 and +30 respectively. France beat Wales 21-16 to stretch their PD to +63 and Ireland needed to win at Twickenham by 34 pts; they won 28-24.

In 2007 France and Ireland against finished level on victories with four apiece. Going into the final round of matches the situation was a three way tie on six points between France (42), Ireland (38) and England (13).

Ireland beat Italy 51-24 giving them a PD of +65 - they conceded an 83rd minute try to Roland de Marigny, converted by Andrea Scanavacca - and meaning that France had to beat Scotland by 24 to take title.

France were leading 39-19 in the 81st minute when Elvis Vermeulen went over to give them the required points difference. England needed then to beat Wales by 57 to take title but lost 19-26.

Last year Wales and England both finished with four wins. After the penultimate round, England had four wins with the chance of a Grand Slam and a PD of +43. Wales were in second place with three wins and a PD of +29. Wales therefore needed to beat England by 15 points to take title and won 30-3.